Solar System News (miscellaneous articles)

[Draggendrop Veteran]

I thought that this would be a good area to place interesting articles related to the solar system...

To start this thread, I found a good editorial which encompasses the future plans for a lunar colony and entities with an interest...and a plan.

 

Op-ed | Getting Serious About the Moon Village

“A Moon Village,” said ESA director-general Johann-Dietrich Woerner, “shouldn’t just mean some houses, a church and a town hall.” It could be beacon of international and even commercial cooperation. Credit: ESA artist's concept of a lunar outpost 

Recently I had the privilege of attending the 66th International Astronautical Congress (IAC) in Jerusalem.

I will confess that in the days leading up to the event, I was feeling rather conflicted. Since I had never been to that part of the world before, I was very much looking forward to the trip. On the other hand, the recent episodes of violence and the often-conflicting guidance about personal safety and security caused me to continually reassess the risks and rewards during each phase of my itinerary.

Now that we are back home, safe and sound, I can honestly say that it was a truly amazing experience, and I am very glad that I went. Having an opportunity to participate in an international conference focused on space exploration in a city having thousands of years of history made for some dramatic contrasts between old and new. And the presence of such an incredible diversity of cultures and religions, with people living and working together in a surprisingly compact geographical area, highlighted some of the challenges and opportunities that we are facing in figuring out how to collaborate on our future space activities.

One of the highlights of the conference itself was a plenary session featuring the leaders of almost all of the major space agencies from around the world. NASA Administrator Charlie Bolden and representatives from Russia, China, the European Space Agency, Japan, India and Israel were seated on the stage and had a chance to share their perspectives and answer questions from the moderators.

I was pleasantly surprised by the spirit of cooperation that all conveyed. One notable exception, which was clearly articulated during the discussion, had to do with the inability of NASA to partner with China on specific space projects, based on constraints in existing law. Other nations, of course, have no such restrictions.

When it came time to talk about plans for the future, I was particularly impressed with the comments made by Johann-Dietrich Woerner, the new director-general of the European Space Agency. Woerner served as chairman of the executive board of DLR, the German Aerospace Center, from March 2007 until June 2015, and took over as ESA chief on July 1.

Woerner’s vision for space exploration involves the establishment of what he calls a “Moon Village” on the far side of the moon. “A Moon Village,” he said, “shouldn’t just mean some houses, a church and a town hall.” Instead, he said, the village “should mean partners from all over the world contributing with robotic and astronaut missions and support communications satellites.”

What appeals to me about that kind of a vision is that it minimizes the requirement for a very prescriptive, top-down management structure with one country specifying the architecture and calling all of the shots. Instead, it would enable countries to participate as much or as little as they chose, based on their capabilities and their interests.

The timing of Woerner’s proposal seems particularly appropriate. We are currently undergoing a dramatic transformation in how space missions are carried out.

Ever since the dawn of the Space Age more than 50 years ago, almost all of the major milestones and historical achievements in space have been accomplished by government space agencies. Even though many companies were actively involved as support contractors, it was the government that was doing most of the planning, direction and execution of missions, whether it involved launching satellites, landing astronauts on the moon or building and operating the International Space Station.

Going forward, that is no longer necessarily going to be the case. In the future, private industry is going to be playing an increasingly important role in space, sometimes as part of a public/private partnership, in other cases by selling products and services to the government, and perhaps on occasion without any government involvement at all.

SpaceX and Orbital ATK are already taking supplies to our astronauts onboard the International Space Station as part of the commercial cargo program. Boeing and SpaceX hope to be transporting crew members to and from the ISS for the commercial crew program as early as 2017. And Bigelow Aerospace plans to start launching and operating commercial space station modules as soon as a commercial crew transportation capability has been successfully demonstrated. Meanwhile, Virgin Galactic and XCOR Aerospace expect to begin commercial operations with their suborbital space tourism vehicles within the next couple of years.

Because of the inherent market uncertainty, one might assume that, at least for the near-future, commercial space ventures will primarily be limited to either suborbital space flights or transportation to and from low Earth orbit (LEO). But in reality, when it comes to space exploration and other missions beyond LEO, some of the most ambitious objectives, as well as many of the more innovative concepts, are being worked on by the private sector. For example:

The Google Lunar X Prize is offering up to $30 million to the first nongovernmental teams to land a rover on the moon, successfully translate across the lunar terrain, and send high-definition video back to Earth.

Moon Express wants to investigate and potentially exploit various kinds of lunar resources.

Golden Spike believes it can make a profit by enabling astronauts from many different countries to conduct scientific expeditions on the moon.

Bigelow Aerospace is looking at soft landing habitable modules on the lunar surface.

Shackleton Energy plans to extract water ice from the poles of the moon and then turn it into rocket fuel.

Planetary Resources and Deep Space Industries are both developing capabilities for asteroid mining.

 

In the end, we know that many of these endeavors are not likely to be successful, either because they will encounter unexpected technical difficulties or because they will run out of money. But it is exciting to see the wide variety of activities that are currently being pursued completely outside of the process for traditional government space programs.

Can any of this be of benefit to a Moon Village initiative? I think it can.

The International Space Exploration Coordination Group published a Global Exploration Roadmap in August 2013, and one of its three mission themes is “Humans to the Lunar Surface.” It notes that, “Many agencies consider human missions to the lunar surface as an essential step in preparation for human Mars missions.”

NASA has certainly expressed support for such missions, although, as Bolden has pointed out on several occasions, “the United States has no intention of leading the effort.” In his remarks at the IAC, Woerner acknowledged that NASA’s recent planning has been focused on going to Mars, rather than returning to the moon. However, in his opinion, “Before going to Mars, we should test what we could do on Mars on the moon.” That makes a lot of sense to me.

So the idea of a Moon Village really resonates with me. But I’d like to suggest a modest change to Woerner’s proposal. Instead of assuming that each inhabitant of the village is a representative of a particular nation, or a government space agency, let’s open it up to commercial entities. After all, every self-respecting village needs a marketplace, where goods and services can be bought, sold or traded for.

The possibilities are limitless.

We’ll need someone to build habitats on the lunar surface, whether they are “space hotels” or more permanent lodging.

Others could focus on extracting water from the lunar regolith, which could then be broken down into hydrogen and oxygen and stored at the neighborhood propellant depot.

Companies could offer electrical power by constructing and operating large solar arrays.

I’m not sure whether lunar farmers will decide to grow potatoes, lettuce, tomatoes or some other celestial delicacies, but the village people will certainly need something to eat, and I’m sure that freeze-dried TV dinners can get old after a while.

Astronauts will likely use rovers to travel long distances across the lunar surface, although it is probably too early to know whether it will be via a Yellow Cab or Uber.

Operating a rocket-powered shuttle bus to and from lunar orbit would make an interesting market niche. But there’s no reason to think that every lunar soil sample would need to be transported all the way back to Earth. Instead, why not assume that the geologists and other scientific researchers could perform their investigations right on site, at the local lunar university?

The bottom line is, as we start to contemplate the idea of establishing villages on the moon, or elsewhere in the solar system, let’s not limit our thinking to government space agencies. Private industry has the potential to play an important role, and it need not be exclusively as a government contractor.

by George Nield — November 10, 2015

http://spacenews.com/op-ed-getting-serious-about-the-moon-village/ 

This summary pretty much shows the intent for a lunar village is real, is being planned and will begin in the very near future.

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Russia touts plan to land a man on the Moon by 2029

File image.

A manned lunar landing by Russian cosmonauts is planned for 2029, the head of the Russian Space Agency Energia said Tuesday.

"A manned flight to the moon and lunar landing is planned for 2029," Vladimir Solntsev said during a space technology conference in Moscow.

The Energia chief, a spacecraft components manufacturer, said Russian scientists were building a new spacecraft made of composites specifically for moon missions. Its maiden flight is scheduled for 2021.

In 2023, the spacecraft is due to dock with the International Space Station, with the first unmanned lunar mission set for 2025.

According to earlier reports, Russia plans to land a Luna-25 research vessel on the south pole of the moon instead of its equator, where all other landings have been centered.

The plan is to explore the internal structure of the Earth's only natural satellite and the impact of the cosmic rays and electromagnetic radiation on its surface, as well as to look for natural resources in the area.

 http://www.space-travel.com/reports/Russia_touts_plan_to_land_a_man_on_the_Moon_by_2029_999.html

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Japan Plans Unmanned Moon Landing

A partial lunar eclipse is seen behind cherry blossoms in Tochigi prefecture, eastern Japan, in April.

 

Agence France-Presse/Getty Images

 

Japan plans to become the fourth country to accomplish an unmanned moon landing.

The government’s space policy committee Wednesday updated the schedule of the nation’s space exploration program and marked 2019 as the year to launch an unmanned lander to the moon. The lander’s development is scheduled to start next year.

In 2013, China became the third country to conduct an unmanned moon landing,following the U.S. and the former Soviet Union. Although Japan is late to the race, getting there is not the sole objective of the mission.

According to the committee, Japan’s lunar lander will be developed with a new technology enabling it to land within 100 meters of its initial mark. Others missed by a far wider margin. Among technologies Japan will use to improve the accuracy will be those from a facial recognition system that will observe the surface of the moon to help make necessary adjustments.

To demonstrate such pinpoint landing precision will help increase Japan’s stature and presence in space exploration, including in future joint efforts with other countries, the committee said.

The government will seek public opinion about the lunar project and space exploration policies and finalize the plan within the year.

 

http://blogs.wsj.com/japanrealtime/2015/11/12/japan-plans-unmanned-moon-landing-in-2019/

as well as this article...
http://phys.org/news/2015-04-japan-moon-mission-space-agency.html

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China Wants To Build A Lunar Base On The Far Side Of The Moon 

photo credit: An illustration of the far side of the moon and Earth in the distance. NASA's Scientific Visualization Studio.

In the early 1970s, future Apollo 17 astronaut Jack Schmitt strongly petitioned NASA to land the Apollo 17 mission on the far side of the moon, ultimately to no avail. His argument was that it would have provided unique science on a fascinating region of the lunar surface, but NASA deemed it too risky for a manned mission at the time.

Now, more than 40 years later, China is planning to achieve this goal in 2018 or 2019, albeit with an unmanned lander and rover, by becoming the first nation to land on the far side of the moon – and they want it to be a stepping stone to eventually having a manned lunar base on the surface.

The stationary lander and rover will jointly be called Chang’e 4, a successor to the Chang’e 3 mission, which touched down on 14 December 2013. This was the first soft-landing on the Moon since the Soviet Union’s Luna 24 in 1976. The European Space Agency (ESA) may play a role in the mission, but it's unsure what yet.

With it, Chang’e 3 carried the Yutu rover, which remained operational on the surface for a few days before running into complications. According to a presentation submitted to the United Nations Office for Outer Space Affairs, China will be hoping to build on this rover technology for the next mission. “[The] Chang’e 4 probe, lander and rover [will] have the same technical status with the Chang’e 3,” they said, but “exploration will be redesigned” and “the payload will be reconfigured.”

 

 
China's Yutu rover, pictured, landed on the Moon on 14 December 2013. CNSA/CCTV.

 

The lander will be accompanied by an orbiting relay satellite in the Earth–Moon Lagrange point 2 (L2) position, into which China sent a test spacecraft last year. For a mission to the far side of the Moon, this is crucial, as the Moon is tidally locked to Earth and the far side never comes into view. This means that all communications must be done via a relay satellite like this.

This was one of the reasons Schmitt was so keen for a mission here. It would have tested how astronauts would cope communicating with Earth in such a manner, which is likely to be necessary on future manned Mars missions.

Perhaps with this in mind, China added in their proposal that the Chang’e 4 mission would serve as “experimental verification for [a] lunar base”. The lunar far side is appealing for a manned base, as some key science could be performed here. For example, as Earth is constantly out of view, the far side is shielded from radio interference on Earth. This means that a radio telescope could have a much clearer view of the universe.

In addition, there are also some features of interest on the far side, such as the South Pole-Aitken basin, while the L2 point has also been considered as a location for a “gateway space station” for manned missions further into the Solar System.

China has made no secret of its desire to cooperate with other nations in space. It is already hoping to be allowed to dock at the International Space Station (ISS) in future, it may be involved in a future Mars mission and now it is considering partnering with ESA for lunar missions. ESA itself has proposed building a “lunar village” recently.

Cooperation with China has been complicated by US space policy, which prohibits NASA from working with the Chinese Space Agency (CNSA) in any way, and thus other countries have been reticent to do so. Perhaps this latest development could represent a thawing of tensions, and lead us closer to a desirable future in which international cooperation among all nations in space is the norm.

 http://www.iflscience.com/china-wants-land-moons-far-side-first-time-and-build-lunar-base

India has expressed an interest in landing a probe as well.........

 

[Draggendrop Veteran]

Astronomers spot most distant object in the solar system

Currently, the object is perched on the outer edge of the Kuiper Belt, the debris-filled region where dwarf planets Pluto and Eris reside.

As of right now, it is the most distant object in the solar system, a sizable space rock 103 times farther away from the sun than the Earth.

The object remains unclassified, cataloged as V774104, and it could be one of the more exciting finds in years -- or it could be just another rock.

Researchers presented the object's discovery on Wednesday to attendees of the 47th annual meeting of the American Astronomical Society's Division for Planetary Sciences, currently being held outside of Washington, D.C.

Currently, the object is perched on the outer edge of the Kuiper Belt, the debris-filled region where dwarf planets Pluto and Eris reside. The object may inhabit the fringes of the Oort cloud, a distant theoretical protoplanetary disk of icy objects.

It's possible the mysterious object hasn't been disturbed for 4.5 billion years, untouched since the solar system's earliest beginnings. If so, it may offer astronomers a unique look at the conditions that birthed our planetary system.

It's also possible that V774104 follows an elliptical orbit and will soon veer much closer to the Sun. If that happens, the object will quickly become less interesting.

"There's no reason to be excited yet," Michael Brown, a planetary scientist at the California Institute of Technology in Pasadena, told Nature.

Astronomers have only identified two objects within the Oort cloud, Sedna and 2012 VP. Both objects swing into the Kuiper Belt for part of their orbits, their path around the sun influenced by the gravitational pull of Neptune.

If V774104 remains unaffected by Neptune, then it will be time to be excited.

 http://www.spacedaily.com/reports/Astronomers_spot_most_distant_object_in_the_solar_system_999.html

In depth article...
http://www.space.com/31100-most-distant-dwarf-planet-found.html

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A Moon Falling Apart: Grooves on Phobos Are a Sign of its Eventual Catastrophic Fate

 

The unusual grooves on Phobos’ surface, such as those on the left side of this image, are now thought to be caused by tidal stress. The large crater Stickney is in the upper portion of the image. Image Credit: NASA/JPL-Caltech/University of Arizona

Phobos is the largest of Mars’ two tiny moons, but 50 million years from now, that may no longer be the case. According to new research, Phobos is gradually being pulled apart by Mars’ gravity and will eventually be destroyed. The unusual long grooves on Phobos’ surface, which have been a puzzle for planetary scientists, are a key piece of evidence that point to eventual structural failure of this little worldlet.

 

The findings are being presented today at this year’s Meeting of the Division of Planetary Sciences of the American Astronomical Society at National Harbor, Maryland.

“We think that Phobos has already started to fail, and the first sign of this failure is the production of these grooves,” said Terry Hurford of NASA’s Goddard Space Flight Center in Greenbelt, Maryland.

 

 

The grooves are now thought to be “stretch marks” caused by tidal forces from the gravitational pull of Mars. A similar process occurs between Earth and the Moon, where tidal forces produce waves in the oceans. Previous theories included the grooves being caused by the impact which created the large Stickney crater on one “end” of Phobos, or by smaller impacts resulting from material being thrown out from Mars during larger impacts on the Martian surface. The problem with the Stickney hypothesis however was that it was later determined that the grooves don’t actually radiate outward from the crater itself as previously thought, but rather from a different focal point on the surface. Therefore, the grooves were not caused by that impact, which scientists think almost destroyed Phobos. But now new modelling studies have shown the grooves to be caused by tidal forces from Mars itself.

Phobos orbits only 3,700 miles (6,000 kilometers) above the surface of Mars, which is closer than any other moon in relation to its planet in the Solar System. Logically, this also makes Phobos more likely to experience tidal forces. As a result, the moon is inning closer to Mars in its orbit, by about 6.6 feet (2 meters) every hundred years. In 30-50 million years, Phobos will likely be pulled apart by Mars’ gravity.

The tidal force theory was actually first proposed when the Viking spacecraft took good close-up images of Phobos and the grooves were clearly seen for the first time. But the idea was rejected because Phobos was thought to be solid throughout; tidal forces wouldn’t be strong enough in that case. But now, the moon is thought to be more like a rubble pile of material being weakly held together, with open spaces within its interior. (Not hollow though, as some people have suggested, and a popular theory in the 1950s and 1960s). This rubble pile is covered by a powdery regolith about 330 feet (100 meters) thick.

 

 
Another good view of both the grooves and the heavily cratered surface of Phobos. Image Credit: NASA/JPL-Caltech/University of Arizona

According to said Erik Asphaug of the School of Earth and Space Exploration at Arizona State University in Tempe and a co-investigator of the study, “The funny thing about the result is that it shows Phobos has a kind of mildly cohesive outer fabric. This makes sense when you think about powdery materials in microgravity, but it’s quite non-intuitive.”

Being less dense makes Phobos more susceptible to tidal forces, and, it seems, will eventually lead to its destruction. There is enough stress to cause the surface to fracture, as is evidenced by the grooves. The stress fractures predicted by computer modelling line up very nicely with the actual fractures seen on Phobos, another indication that the tidal force theory is correct. Another observation, that some grooves are younger than others, also fits.

This kind of tidal force has been seen elsewhere in the Solar System as well. Neptune’s largest moon Triton, for example, is slowly losing its orbit and falling inward toward the planet, and it displays similar fractures to those seen on Phobos, as well as blocky outcrops, ridges, troughs, furrows, hollows, plateaus, icy plains and few craters. Triton is also famous for its nitrogen geysers, a form of cryovolcanism. Triton will eventually share the same fate as Phobos at an estimated 3.6 billion years from now. Triton is the only moon in the Solar System known to orbit in the direction opposite of its planet’s rotation.

More data at the link...
 http://www.americaspace.com/?p=88449#more-88449

[Draggendrop Veteran]

Titan, Saturn's largest moon......first some data...

Titan (or Saturn VI) is the largest moon of Saturn. It is the only natural satellite known to have a dense atmosphere,^[9]and the only object other than Earth where clear evidence of stable bodies of surface liquid has been found.^[10]

Titan is the sixth ellipsoidal moon from Saturn. Frequently described as a planet-like moon, Titan's diameter is 50% larger than Earth's natural satellite, the Moon, and it is 80% more massive. It is the second-largest moon in the Solar System, after Jupiter's moon Ganymede, and is larger by volume than the smallest planet, Mercury, although only 40% as massive. Discovered in 1655 by the Dutch astronomer Christiaan Huygens,^[11][12] Titan was the first known moon of Saturn, and the fifth known satellite of another planet.^[13]

Titan is primarily composed of water ice and rocky material. Much as with Venus before the Space Age, the dense opaque atmosphere prevented understanding of Titan's surface until new information accumulated when the Cassini–Huygens mission arrived in 2004, including the discovery of liquid hydrocarbon lakes in Titan's polar regions. The geologically young surface is generally smooth, with few impact craters, although mountains and several possiblecryovolcanoes have been found.^[14][15]

The atmosphere of Titan is largely nitrogen; minor components lead to the formation of methane–ethane clouds and nitrogen-rich organic smog. The climate—including wind and rain—creates surface features similar to those of Earth, such as dunes, rivers, lakes, seas (probably of liquid methane–ethane), and deltas, and is dominated by seasonal weather patterns as on Earth. With its liquids (both surface and subsurface) and robust nitrogen atmosphere, Titan's methane cycle is analogous to Earth's water cycle, although at a much lower temperature.

 https://en.wikipedia.org/wiki/Titan_(moon)

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Mighty winds fuel megastorms on Titan

WEATHER ADVISORY  A 1,200-kilometer-wide storm blowing across Titan, seen in this 2010 image from the Cassini spacecraft, might be similar to squalls on Earth, new research suggests.

OXON HILL, Md. — Beneath the orange haze of Saturn’s moon Titan, methane rains from the sky and pools in lakes — and might even burst forth from massive storm squalls like those seen on Earth.

Titan has garden-variety thunderstorms that bring a bit of rain, then disappear. Now, the Cassini orbiter has seen phenomena that can’t be explained by these run-of-the-mill storms: cloud outbursts, liquid-carved channels and dark regions “reminiscent of rain falling on a parking lot,” planetary scientist Scot Rafkin reported November 11 at a meeting of the American Astronomical Society’s Division for Planetary Sciences.

Using computer simulations of cloud systems, Rafkin found that with a bit of wind shear, Titan could produce giant, long-lasting storm systems. On Titan, though, these storms would be beefed up: The squalls would last for longer than 24 hours and travel for more than 1,000 kilometers while dumping a couple of meters’ worth of methane from clouds three times as high as their counterparts on Earth.

Such storms would cause massive flooding on Earth as well as on Titan. “It’s more than enough to carve the river channels and fluvial features we see on the surface,” says Rafkin, of the Southwest Research Institute in Boulder, Colo. Strong gusts might also explain dunes that should have trouble forming with Titan’s typically weak winds. These squalls are “strong enough and moving in the right direction to coincide with dunes in the tropics,” Rafkin says.

 https://www.sciencenews.org/article/mighty-winds-fuel-megastorms-titan?tgt=nr

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NASA’s Cassini Finds Monstrous Ice Cloud in Titan’s South Polar Region

 

New observations made near the south pole of Titan by NASA’s Cassini spacecraft add to the evidence that winter comes in like a lion on this moon of Saturn.

Scientists have detected a monstrous new cloud of frozen compounds in the moon’s low- to mid-stratosphere – a stable atmospheric region above the troposphere, or active weather layer.

 

 
 

As winter sets in at Titan’s south pole, a cloud system called the south polar vortex (small, bright “button”) has been forming, as seen in this 2013 image.

Credits: NASA/JPL-Caltech/Space Science Institute

 

Cassini’s camera had already imaged an impressive cloud hovering over Titan’s south pole at an altitude of about 186 miles (300 kilometers). However, that cloud, first seen in 2012, turned out to be just the tip of the iceberg. A much more massive ice cloud system has now been found lower in the stratosphere, peaking at an altitude of about 124 miles (200 kilometers).

The new cloud was detected by Cassini’s infrared instrument – the Composite Infrared Spectrometer, or CIRS – which obtains profiles of the atmosphere at invisible thermal wavelengths. The cloud has a low density, similar to Earth’s fog but likely flat on top.

For the past few years, Cassini has been catching glimpses of the transition from fall to winter at Titan’s south pole – the first time any spacecraft has seen the onset of a Titan winter. Because each Titan season lasts about 7-1/2 years on Earth’s calendar, the south pole will still be enveloped in winter when the Cassini mission ends in 2017.

“When we looked at the infrared data, this ice cloud stood out like nothing we’ve ever seen before,” said Carrie Anderson of NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “It practically smacked us in the face.”

Anderson is presenting the findings at the annual Meeting of the Division of Planetary Sciences of the American Astronomical Society at National Harbor, Maryland, on Nov. 11.

The ice clouds at Titan’s pole don’t form in the same way as Earth’s familiar rain clouds.

For rain clouds, water evaporates from the surface and encounters cooler temperatures as it rises through the troposphere. Clouds form when the water vapor reaches an altitude where the combination of temperature and air pressure is right for condensation. The methane clouds in Titan’s troposphere form in a similar way.

However, Titan’s polar clouds form higher in the atmosphere by a different process. Circulation in the atmosphere transports gases from the pole in the warm hemisphere to the pole in the cold hemisphere. At the cold pole, the warm air sinks, almost like water draining out of a bathtub, in a process known as subsidence.

The sinking gases – a mixture of smog-like hydrocarbons and nitrogen-bearing chemicals called nitriles – encounter colder and colder temperatures on the way down. Different gases will condense at different temperatures, resulting in a layering of clouds over a range of altitudes.

Cassini arrived at Saturn in 2004 – mid-winter at Titan’s north pole. As the north pole has been transitioning into springtime, the ice clouds there have been disappearing. Meanwhile, new clouds have been forming at the south pole. The build-up of these southern clouds indicates that the direction of Titan’s global circulation is changing.

“Titan's seasonal changes continue to excite and surprise," said Scott Edgington, Cassini deputy project scientist at NASA's Jet Propulsion Laboratory (JPL) in Pasadena, California. "Cassini, with its very capable suite of instruments, will continue to periodically study how changes occur on Titan until its Solstice mission ends in 2017.”

The size, altitude and composition of the polar ice clouds help scientists understand the nature and severity of Titan’s winter. From the ice cloud seen earlier by Cassini’s camera, scientists determined that temperatures at the south pole must get down to at least -238 degrees Fahrenheit (-150 degrees Celsius).

The new cloud was found in the lower stratosphere, where temperatures are even colder. The ice particles are made up of a variety of compounds containing hydrogen, carbon and nitrogen.

Anderson and her colleagues had found the same signature in CIRS data from the north pole, but in that case, the signal was much weaker. The very strong signature of the south polar cloud supports the idea that the onset of winter is much harsher than the end.

“The opportunity to see the early stages of winter on Titan is very exciting,” said Robert Samuelson, a Goddard researcher working with Anderson. “Everything we are finding at the south pole tells us that the onset of southern winter is much more severe than the late stages of Titan’s northern winter.”

The Cassini-Huygens mission is a cooperative project of NASA, ESA (European Space Agency) and the Italian Space Agency. JPL manages the mission for NASA's Science Mission Directorate in Washington. The CIRS team is based at Goddard.

http://www.nasa.gov/feature/goddard/monstrous-ice-cloud-in-titans-south-polar-region

This 2012 close-up offers an early snapshot of the changes taking place at Titan’s south pole. Cassini’s camera spotted this impressive cloud hovering at an altitude of about 186 miles (300 kilometers). Cassini’s thermal infrared instrument has now detected a massive ice cloud below it.

Credits: NASA/JPL-Caltech/Space Science Institute

 

to see this storm rotating...check this link....
http://www.pcmag.com/slideshow/story/335468/10-creepy-but-spectacular-shots-of-saturn-s-moon-titan/5

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Dunelands of Titan 

Saturn's frigid moon Titan has some characteristics that are oddly similar to Earth, but still slightly alien. It has clouds, rain and lakes (made of methane and ethane), a solid surface (made of water ice), and vast dune fields (filled with hydrocarbon sands).

The dark, H-shaped area seen here contains two of the dune-filled regions, Fensal (in the north) and Aztlan (to the south).

Cassini's cameras have frequently monitored the surface of Titan (3200 miles or 5150 kilometers across) to look for changes in its features over the course of the mission. Any changes would help scientists better understand different phenomena like winds and dune formation on this strangely earth-like moon.

For a closer view of Fensal-Aztlan, see PIA07732.

This view looks toward the leading side of Titan. North on Titan is up. The image was taken with the Cassini spacecraft narrow-angle camera on July 25, 2015 using a spectral filter sensitive to wavelengths of near-infrared light centered at 938 nanometers.

The view was obtained at a distance of approximately 450,000 miles (730,000 kilometers) from Titan and at a Sun-Titan-spacecraft, or phase, angle of 32 degrees. Image scale is 3 miles (4 kilometers) per pixel.

The Cassini mission is a cooperative project of NASA, ESA (the European Space Agency) and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colorado.

For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov or http://www.nasa.gov/cassini . The Cassini imaging team homepage is at http://ciclops.org.

Credit: NASA/JPL-Caltech/Space Science Institute

http://www.nasa.gov/image-feature/jpl/pia18341/dunelands-of-titan

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 Titan's Accent Mark

 

A coincidence of viewing angle makes Pandora appear to be hovering over Titan, almost like an accent mark.

Little Pandora is much closer to Cassini than hazy Titan in this view. (Titan is nearly three times farther away.) Even so, Titan (3,200 miles or 5,150 kilometers across) dwarfs Pandora (50 miles or 81 kilometers across). This gives us some sense of the diversity in sizes, and shapes, of Saturn's many moons.

North on Titan is up and rotated 19 degrees to the right. The image was taken in visible green light with the Cassini spacecraft narrow-angle camera on July 4, 2015.

The view was acquired at a distance of approximately 1.2 million miles (1.9 million kilometers) from Titan. Image scale is 7 miles (12 kilometers) per pixel on Titan. Pandora is at a distance of 436,000 miles (698,000 kilometers) away from the spacecraft. The scale on Pandora is about 3 miles (4 kilometers) per pixel.

The Cassini mission is a cooperative project of NASA, ESA (the European Space Agency) and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colorado.

For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov or http://www.nasa.gov/cassini . The Cassini imaging team homepage is at http://ciclops.org .

Credit: NASA/JPL-Caltech/Space Science Institute

http://www.nasa.gov/image-feature/jpl/pia18338/titans-accent-mark

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Beside a Giant

Saturn's largest moon, Titan, looks small here, pictured to the right of the gas giant in this Cassini spacecraft view.

Titan (3,200 miles, or 5,150 kilometers across) is in the upper right. Saturn's rings appear across the top of the image, and they cast a series of shadows onto the planet across the middle of the image.

The moon Prometheus (53 miles, or 86 kilometers across) appears as a tiny white speck above the rings in the far upper right of the image. The shadow cast by Prometheus can be seen as a small black speck on the planet on the far left of the image, between the shadows cast by the main rings and the thin F ring. The shadow of the moon Pandora also can be seen on the planet south of the shadows of all the rings, below the center of the image towards the right side of the planet. Pandora is not shown here.

This view looks toward the southern, unilluminated side of the rings from about 1 degree below the ringplane.

The image was taken with the Cassini spacecraft wide-angle camera on Jan. 5, 2012 using a spectral filter sensitive to wavelengths of near-infrared light centered at 752 nanometers. The view was acquired at a distance of approximately 426,000 miles (685,000 kilometers) from Saturn and at a Sun-Saturn-spacecraft, or phase, angle of 20 degrees. Image scale is 23 miles (37 kilometers) per pixel on Saturn. The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo.

Image credit: NASA/JPL-Caltech/Space Science Institute

 http://www.nasa.gov/multimedia/imagegallery/image_feature_2185.html

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An up-close view of Titan's surface as captured by the Huygens lander.

(Credit: ESA/NASA/JPL/University of Arizona)

 

An up-close view of the oceans and lakes on Titan's surface as captured by radar in 2006. 

(Credit: NASA/JPL/Space Science Institute)

Titan slide show
http://www.esa.int/Our_Activities/Space_Science/Cassini-Huygens/Titan_first_images_-_slideshow

Titan raw images...ESA
http://esamultimedia.esa.int/docs/titanraw/index.htm

What Huygens Saw On Titan - New Image Processing | Video, 4:40 min..real neat.....

 

Incredible HD Videos of Saturn's Moon Titan, video is 1:59 min

 

[Draggendrop Veteran]

ESA plans for Rosetta’s grand finale on comet 67P

 

Artist’s concept of the Rosetta spacecraft with a real image of comet 67P in the background. Credit: ESA/ATG medialab/Rosetta/NAVCAM

European Space Agency flight controllers are plotting to send the Rosetta spacecraft on a controlled descent to the surface of comet 67P/Churyumov-Gerasimenko next year to join the Philae landing probe, which made a bouncy touchdown on the comet’s craggy nucleus one year ago this week.

Rosetta begins an extended mission in December, with funding and fuel available to continue the spacecraft’s study of the comet through September 2016.

“We recently celebrated our first year at the comet and we are looking forward to the scientific discoveries the next year will bring,” said Matt Taylor, ESA’s Rosetta project scientist, in a statement.

After a 10-year cruise through the inner solar system, Rosetta arrived in the vicinity of the comet in August 2014, and it dropped the Philae lander to comet 67P on Nov. 12, 2014. The comet’s orbit took it closest to the sun Aug. 13 — a point known as perihelion — as Rosetta backed off from the nucleus to avoid a potentially hazardous cloud of dust and gas growing around the comet.

Rosetta is now slowly moving back toward the comet as activity dies off as its distance from the sun grows. The spacecraft reached a point 170 kilometers, or 105 miles, from the nucleus Thursday, and Rosetta will go much closer in the coming months.

“Next year, we plan to do another far excursion, this time through the comet’s tail and out to 2,000 kilometers (about 1,200 miles),” Taylor said in a press release. “To complement that, we hope to make some very close flybys towards the end of the mission, as we prepare to put the orbiter down on the comet.”

The close flybys will give scientists a last shot at restoring a communications link with Philae, which mission control has not heard from since July.

Philae’s anchoring harpoons and ice screws failed to discharge when it contacted the lander’s targeted touchdown site — a relatively flat sunlit area named Agilkia — and the probe rebounded, bounced and ended up up lodged against a cliff.

The wall of rock blocked sunlight from reaching Philae’s body-mounted solar arrays, and the lander drained its batteries two days later. Scientists say the lander still collected 80 percent of its planned science data during the abbreviated mission.

Engineers were optimistic the lander would awaken as the comet swept closer to the sun, warming the temperature inside Philae’s internal electronics bay and putting more sunlight on the solar panels. Philae’s team was vindicated in June, when the probe radioed home via its Rosetta mothership.

But Philae only made intermittent contact with the ground over the following month, and it went silent July 9.

Temperatures will likely be too cold for Philae in January, officials said.

 

 
This mosaic of images from Rosetta’s OSIRIS science camera area shows the area surrounding Philae’s first touchdown point, Agilkia (circled) on comet 67P/Churyumov–Gerasimenko. The large depression is the Hatmehit region. The dashed line marks the comet’s equator. This image is a composite of five frames from the OSIRIS narrow-angle camera. Credit: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA

Engineers placed Rosetta in hibernation on approach to comet 67P, but its current trajectory will take it even farther from the sun as the comet heads back into the cold depths of the outer solar system beyond Jupiter in its 6.5-year orbit.

Officials are inclined to conclude Rosetta’s mission next year due to three factors:

• Communications with Rosetta will be complicated in October 2016, when the comet and the Sun appear near the position in the sky as viewed from Earth, an event called solar conjunction.
• Rosetta will be low on fuel, leaving limited options for a secondary mission if the spacecraft can be put to sleep in a power-saving mode.
• The spacecraft was never designed to withstand a second hibernation, and there are questions whether Rosetta can survive a second sojourn through the cold outer solar system.

While details of the end-of-mission plan are yet to be finalized, ground controllers have begun thinking of how to delicately guide Rosetta to a “controlled impact” on the comet, officials said.

Managers at the European Space Operations Center in Germany have discussed the option to put Rosetta on the comet for months — officials talked about the idea with reporters after Philae’s landing a year ago — but the plan began to crystallize in recent weeks.

“We are still discussing exactly what the final end of mission scenario will involve,” said Sylvain Lodiot, ESA’s Rosetta spacecraft operations manager at ESOC. “It is very complex and challenging, even more so even than the lander delivery trajectory our flight dynamics teams had to plan for delivering Philae.

“The schedule we’re looking at would first involve a move into highly elliptical orbits — perhaps as low as 1 kilometer (about 3,300 feet) — in August, before moving out to a more distant point for a final approach that will set Rosetta on a slow collision course with the comet at the end of September.”

Taylor compared Rosetta’s mission narrative to a soap opera, and he expects more drama in the craft’s final months. There is some hope Rosetta could operate on the comet’s surface after a soft impact, but such an outcome would require meticulous planning, and a bit of luck.

Lodiot said the chances of the spacecraft surviving the touchdown are remote.

“We’ll control Rosetta all the way down to the end, but once on the surface it will be highly improbable that we’ll be able to ‘speak’ to it anymore,” Lodiot said in an ESA statement.

With a finely-tuned high-gain antenna, which must be aimed at Earth to send and receive large volumes of data, and big solar panels stretching 32 meters (105 feet) tip-to-tip, Rosetta was never designed for such a maneuver. Many of the spacecraft’s appendages could be crushed during the landing attempt.

“Jokingly, around a bar, one might be able to say, ‘Oh, maybe we can try and tilt the solar arrays and get the antenna pointed in the right direction,'” Taylor said in an interview with Spaceflight Now earlier this year. “But that’s the thing of fantasy and comedic discussion at the moment. The key thing is depositing the orbiter on the comet and gaining those very, very close observations.”

The close-up encounters in the final throes of the mission will give Rosetta’s OSIRIS camera extraordinary views of the comet.

“We’ll get down six times as close as where we’ve been,” Taylor said. “That’s going to be pretty damn good. We’re talking centimetre resolution.”

Mark McCaughrean, a senior science advisor to ESA, said Rosetta’s own landing on the comet would be a “fitting end to an astronishing journey.”

“This story is not over. There’s just something about Rosetta,” Taylor says. “I wouldn’t want to say, ‘Yeah, we’re definitely going to try to steer the antenna and do all this,’ but one can imagine, just from the theatrics of this mission, this may be something we’d look into, because why not?”

http://spaceflightnow.com/2015/11/14/esa-plans-for-rosettas-grand-finale-on-comet-67p/

http://spaceref.com/comets/philae-lander-one-year-on-a-comet.html

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 U.S.-Russian talks on Venus mission resume

NASA’s Magellan mission mapped Venus in radar imagery, revealing the planet’s global surface topography for the first time. Credit: NASA/JPL-Caltech

NASA has resumed discussions with Russia on a potential joint robotic mission to Venus in the late 2020s after the Ukraine crisis stalled the partnership, according to scientists involved in the talks.

Russian scientists have studied the Venera-D mission to Venus more than a decade as a follow-up to the Soviet-era Venera and Vega probes to the second rock from the sun.

Rob Landis, a program executive at NASA Headquarters, told a meeting of the Venus Exploration Analysis Group last month that the discussions are taking a “100,000-foot view” of the mission.

NASA has only committed to a year-long feasibility study, which will produce a report for top NASA and Russian managers to decide whether to pursue a cooperative mission to Venus, Landis said Oct. 27 at the VEXAG meeting in Washington.

The joint science definition team met in Moscow from Oct. 5-8, and scientists plan two more face-to-face meetings in the Russian capital over the next year. Scientists from the Moscow-based Space Research Institute, known by the Russian acronym IKI, are in charge of the Venera-D concept.

Russian officials envision the Venera-D mission as a combined orbiter and lander. Scientists are also studying whether the mission could accommodate a balloon to loiter in the Venusian atmosphere for several days, measuring the sweltering planet’s climate patterns and winds.

“We made a lot of progress,” said David Senske, a scientist at NASA’s Jet Propulsion Laboratory who is the U.S. co-chair of the Venera-D science definition team. “We heard a lot about what they had in mind. We’ve been told this is an IKI/Roscosmos endeavor, so they’re in the driver’s seat.”

Senske said the U.S. role in the science definition team is to steer the Venera-D mission’s objectives toward addressing NASA priorities and answering questions posed by the last planetary science decadal survey, a document published by the National Research Council that guides U.S. solar system exploration.

The October meeting came after the potential Venera-D partnership was put on hold following Russia’s annexation of Crimea in early 2014.

A U.S. government directive for NASA to curtail its cooperation with Russia in April 2014 excluded large projects, such as the International Space Station and Russia’s research instrument aboard the Curiority Mars rover. But the policy forced the Venera-D science definition team to suspend their work before it even started.

 

 
Artist’s concept of the Venera-D spacecraft. Credit: NASA/IKI/David Senske

“Almost two years ago, NASA and Roscosmos decided to stand up a joint science definition team,” Senske said. “We had just gotten our work going when we were told stand down, but in August (of) this year, we were told we were back in business again.”

Russia’s federal space program initially included the Venera-D mission as a core component, assuring the project of Russian government funding. But Senske said the Russian space agency, Roscosmos, has now asked scientists to formally propose the Venera-D mission before it will be considered for full development.

NASA participation in the mission could reduce Venera-D’s cost to the Russian government, and IKI scientists have scaled back the scope of the mission.

The mission includes a spacecraft in a 24-hour orbit around Venus, and a probe that will descend through the planet’s smothering atmosphere and operate on the surface for up to several hours.

Russian scientists initially planned a more sturdy lander — the “D” in Venera-D stands for the Russian word for long-lived — but designing and building a spacecraft to survive for multiple days on Venus turned out to be too costly.

“When they looked at that in detail, they discovered that was a bridge too far. They wanted to get 24 hours or more (from the lander), but in order to fit into their cost envelope, they’re looking at more of a Vega-type lander,” Senske said, referring to the Soviet Union’s Vega missions to Venus in the 1980s.

Russia’s last Venus missions launched in 1984 after launching a series of Venus probes beginning in 1961.

The Venera-D lander would likely focus on atmospheric observations, surface imagery and composition measurements, and searching for volcanic activity. Venera-D’s orbiter would look at Venus’ upper atmosphere, cloud patterns, super-rotating winds and the planet’s runaway greenhouse effect, which gives Venus surface temperatures of nearly 900 degrees Fahrenheit (nearly 500 degrees Celsius).

Launch of the Venera-D mission will not occur before 2025, according to Lev Zelyony, IKI’s director, who was quoted in a story by Russia’s Interfax news agency.

Tasks for the science definition team include identifying the Venera-D mission’s science goals and technological needs. The discussions will also determine what NASA could contribute to the mission, assuming it goes forward.

A final report from the science definition team to NASA and IKI is due Sept. 30, 2016.

http://spaceflightnow.com/2015/11/12/u-s-russian-talks-on-venus-mission-resume/

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Earth Stole Water and More from the Young Moon 

An artist's image of a collision between two planetary bodies. A similar crash likely formed the Earth and moon. New research suggests that the Earth took water and other volatiles from the moon after the collision.
Credit: NASA/JPL-Caltech

Earth may have stolen away water that would otherwise have gone to the moon.

New research suggests that after the impact that formed the Earth and its moon, our planet may have snatched up easily vaporized material known as volatiles, including water and other molecules. As the newly formed moon moved away, it may have spurned the remaining material available, casting it back toward Earth.

"The idea for decades has been that the vaporized volatiles escaped, and that's why the moon lacks them," Robin Canup, of the Southwest Research Institute in Colorado, said on Tuesday (Nov. 10) in a news briefing at the annual meeting of the Division for Planetary Sciences of the American Astronomical Society, in National Harbor, Maryland. Canup was the lead author of a research paper that proposed the material didn't vaporize, but instead hung around. [Water on the Moon: The Search in Photos]

"We're exploring an alternative," she said.

 

 

Early in the life of the solar system, a young, volatile-rich protoplanet floated near what is Earth's orbit today. A violent collision with another massive object, called Theia, is thought to have shattered that growing world, allowing the formation of the Earth and moon.

Rocks found on the moon bear a striking similarity to those on Earth, but with one difference: They are noticeably lacking in volatile material, such as water, zinc, sodium and potassium. For years, scientists proposed that the heat from the crash with Theia might have vaporized the volatiles, allowing them to completely escape the system. But Canup and her team argue that very little of that material would have been lost, because the speed necessary to leave Earth's gravity would be so high. If that material stuck around, it would have been available for both the Earth and the moon to gather up. [Evolution of the Moon: A Visual Timeline (Gallery)]

In only a handful of years, both the Earth and moon would have re-formed their cores. The remaining material, including the volatiles, would have orbited the larger Earth in a ring system similar to Saturn's. For a brief window of time, the moon would have collected some of the lighter stuff, a process that could have led to a volatile-rich core for the satellite. At the same time, the larger Earth would have gathered more of the volatile mass than its younger sibling did.

"But the process doesn't persist indefinitely," so the moon eventually stopped collecting volatiles, Canup said.

Since its formation, the moon has been steadily orbiting farther and farther from Earth; today, it moves away at a rate of 1.5 inches (4 centimeters) each year. As that process occurred in the first few decades of the moon's lifetime, the satellite quickly lost the ability to accrete water and other lighter materials from Earth's ring. Instead, as the dust and gas of the ring interacted with the gravity of the satellite, those materials were flung back toward the planet rather than falling onto the moon.

The moon would take the last half of its mass from the inner region of Earth's disk, which would have been too hot to contain water and other volatile material, Canup said. The result would be a rocky crust on the moon ranging from 60 to 300 miles (100 to 500 kilometers) thick. The layers under that crust could contain more of the missing materials.

The team reached its new results, which were published online in the journal Nature Geoscience, by combining models of heat and chemistry with the previously utilized models of motion, the first time this had been done. The chemistry models were developed especially for this work, and were built to simulate the oxygen-dominated disk that would surround the new Earth, rather than the hydrogen-dominated disk surrounding the sun.

 http://www.space.com/31115-earth-stole-moon-water.html

[Draggendrop Veteran]

Upgrade Helps NASA Study Mineral Veins on Mars

This view from the Mars Hand Lens Imager (MAHLI) on the arm of NASA's Curiosity Mars rover shows a combination of dark and light material within a mineral vein at a site called "Garden City" on lower Mount Sharp. Image courtesy NASA/JPL-Caltech/MSSS. For a larger version of this image please go here.

Scientists now have a better understanding about a site with the most chemically diverse mineral veins NASA's Curiosity rover has examined on Mars, thanks in part to a valuable new resource scientists used in analyzing data from the rover. Curiosity examined bright and dark mineral veins in March 2015 at a site called "Garden City," where some veins protrude as high as two finger widths above the eroding bedrock in which they formed.

The diverse composition of the crisscrossing veins points to multiple episodes of water moving through fractures in the bedrock when it was buried. During some wet periods, water carried different dissolved substances than during other wet periods. When conditions dried, fluids left clues behind that scientists are now analyzing for insights into how ancient environmental conditions changed over time.

"These fluids could be from different sources at different times," said Diana Blaney, a Curiosity science team member at NASA's Jet Propulsion Laboratory, Pasadena, California. "We see crosscutting veins with such diverse chemistry at this localized site. This could be the result of distinct fluids migrating through from a distance, carrying chemical signatures from where they'd been."

Researchers used Curiosity's laser-firing Chemistry and Camera (ChemCam) instrument to record the spectra of sparks generated by zapping 17 Garden City targets with the laser. The unusually diverse chemistry detected at Garden City includes calcium sulfate in some veins and magnesium sulfate in others. Additional veins were found to be rich in fluorine or varying levels of iron.

As researchers analyzed Curiosity's observations of the veins, the ChemCam team was completing the most extensive upgrade to its data-analysis toolkit since Curiosity reached Mars in August 2012.

They more than tripled - to about 350 - the number of Earth-rock geochemical samples examined with a test version of ChemCam. This enabled an improvement in their data interpretation, making it more sensitive to a wider range of possible composition of Martian rocks.

Blaney said, "The chemistry at Garden City would have been very enigmatic if we didn't have this recalibration."

The Garden City site is just uphill from a mudstone outcrop called "Pahrump Hills," which Curiosity investigated for about six months after reaching the base of multi-layered Mount Sharp in September 2014.

The mission is examining ancient environments that offered favorable conditions for microbial life, if Mars has ever hosted any, and the changes from those environments to drier conditions that have prevailed on Mars for more than 3 billion years. Curiosity has found evidence that base layers of Mount Sharp were deposited in lakes and rivers. The wet conditions recorded by the Garden City veins existed in later eras, after the mud deposited in lakes had hardened into rock and cracked.

Eye-catching geometry revealed in images of the veins offers additional clues. Younger veins continue uninterrupted across intersections with veins that formed earlier, indicating relative ages.

ChemCam provides the capability of making distinct composition readings of multiple laser targets close together on different veins, rather than lumping the information together. The chemistry of these veins is also related to mineral alteration observed at other places on and near Mount Sharp. What researchers learned here can be used to help understand a very complex fluid chemical history in the region. Since leaving Garden City, Curiosity has climbed to higher, younger layers of Mount Sharp.

http://www.marsdaily.com/reports/Upgrade_Helps_NASA_Study_Mineral_Veins_on_Mars_999.html

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A Large Filament 

GREAT CIRCLE OF MAGNETISM: A dark filament of magnetism in the sun's southern hemisphere has curled upon itself to form a circle of gargantuan porportions. The circumference of the ring is almost a million kilometers--dimensions that make it an easy target for backyard solar telescopes. Amateur astronomer Peter Desypris sends this picture from Athens, Greece:

 

 

"I could not fit the entire ring in my telescope's field of view," says . "This is a mosaic of two images."

Bushy magnetic filaments are often unstable, and they have a tendency to collapse. Filaments crashing to the surface of the sun can cause of a type of explosion called a Hyder flare. Any flare from this filament could be extra-energetic as it releases the tension stored in its million-km coil. Amateur astronomers are encouraged to monitor the structure for possible developments.

http://www.spaceweather.com/

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 Planetary Resources aims to mine asteroids – and possibly save humanity

Article by Bryan Clark which shows the impact space mining will have.

Back in May I wrote about House Resolution 2262 – or the SPACE Act – which effectively cleared any regulatory hurdles that kept companies from mining in space. I sat down with the President and Chief Engineer ofPlanetary Resources, a company that plans to do just that.

It’s my nature to be skeptical, both on a personal and professional level. When you hear that a company wants to travel to space and “drill, baby drill,” it all sounds decidedly science fiction.

My time with Chris Lewicki, brief as it was, changed my mind.

“Most people think this is science fiction and it probably won’t happen anytime soon,” said Lewicki. “Everything that was a breakthrough was once a crazy idea. Those things happened over night, but they have years and years of development behind them. This has something that’s been happening for years.”

You see, it turns out that most of the science needed to complete these missions already exists. The remaining technical challenges are what Lewicki and and his team are working to overcome.

They’re not alone.

The effort is a sort of communal one – featuring names like NASA, SpaceX and Virgin Galactic. While the teams aren’t implicitly connected, they aren’t acting entirely independently, either. It’s a sort of space-aged altruism, if you will.

The goal for Planetary Resources is lofty. They intend to prospect, mine and carry tons of precious resources from near space back to a planet where many of these metals and precious minerals are scarce.

Lewicki isn’t deluded in his thinking that it’ll happen overnight.

But when could we see actual the first companies lay interstellar claims and start bringing the real prize — gold, diamonds, platinum — back home?

“Between three to five years from now we will have proven out all the commercial approaches and the very low cost and innovative methods we’re developing that’ll allow us to make that first visit to the asteroid before the end of the 2010s,” he said. “Mining could begin in just a few years after that once we’ve located the first asteroid that has that resource on it.”

If you’re counting them out, don’t.

The team is led by some of the best and brightest minds in the aerospace industry including Lewicki himself, a former NASA engineer.

Additionally, Planetary Resources features a who’s-who list of advisors and investors, including Larry Page, Richard Branson and Eric Schmidt.

The implications of space mining may far extend the profit motive, in whatever sense that’s possible.

In fact, the depth of the technology Planetary Resources, and others are developing could, in fact, lead us to colonizing other planets.

Lewicki recognizes that this could be the key to colonies on Mars — or elsewhere — in the (relatively) near future.

“It is the way by which humanity will expand off this planet and be able to do that sustainably and permanently,” he says, before going on to mention that extracting water would allow us to use the hydrogen and water as a way to effectively “refuel” on other planets or asteroids, rather than having to build a new rocket, as has been the case for the past 50 years.

Toward the final frontier

Facilitating the survival of the human race is a noble cause and a great narrative, but make no mistake about it, there are still massive fortunes to be made in space.

The website Asterank bills itself as a “scientific and economic database of over 600,000 asteroids.” It also tracks how valuable they are.

 

 

Take Ryugu, for example, with an estimated value of over $95 billion alone. According to Asterank, the valuable metal deposits — iron, nickel and cobalt — as well as the presence of hydrogen and water — the ingredients to make rocket fuel — are no doubt responsible for the lofty estimate.

If you believe NASA, or TechCrunch, this is easily a multi-trillion dollar market. Some asteroids listed on Asterank are valued at above $100 trillion dollars alone.

With this much money on the line, you can be sure one or, more probable, a collective group of these organizations will find a way to make reality of science fiction sooner rather than later and that’s a good thing. Because if Chris Lewicki is correct, the future of humanity could just depend on it.

 http://thenextweb.com/insider/2015/11/13/planetary-resources-aims-to-mine-asteroids-possibly-save-humanity/

On the Moon or Mars, for example, SpaceX, Bigelow and Planetary Resources would complement each other.

[Draggendrop Veteran]

Curiosity Heads Toward Active Dunes

 

Dunes Ahead    NASA

On its way to higher layers of the mountain where it is investigating how Mars' environment changed billions of years ago, NASA's Curiosity Mars rover will take advantage of a chance to study some modern Martian activity at mobile sand dunes.

In the next few days, the rover will get its first close-up look at these dark dunes, called the "Bagnold Dunes," which skirt the northwestern flank of Mount Sharp. No Mars rover has previously visited a sand dune, as opposed to smaller sand ripples or drifts. One dune Curiosity will investigate is as tall as a two-story building and as broad as a football field. The Bagnold Dunes are active: Images from orbit indicate some of them are migrating as much as about 3 feet (1 meter) per Earth year. No active dunes have been visited anywhere in the solar system besides Earth.

"We've planned investigations that will not only tell us about modern dune activity on Mars but will also help us interpret the composition of sandstone layers made from dunes that turned into rock long ago," said Bethany Ehlmann of the California Institute of Technology and NASA's Jet Propulsion Laboratory, both in Pasadena, California.

As of Monday, Nov. 16, Curiosity has about 200 yards or meters remaining to drive before reaching "Dune 1." The rover is already monitoring the area's wind direction and speed each day and taking progressively closer images, as part of the dune research campaign. At the dune, it will use its scoop to collect samples for the rover's internal laboratory instruments, and it will use a wheel to scuff into the dune for comparison of the surface to the interior.

Curiosity has driven about 1,033 feet (315 meters) in the past three weeks, since departing an area where its drill sampled two rock targets just 18 days apart. The latest drilled sample, "Greenhorn," is the ninth since Curiosity landed in 2012 and sixth since reaching Mount Sharp last year. The mission is studying how Mars' ancient environment changed from wet conditions favorable for microbial life to harsher, drier conditions.

Before Curiosity's landing, scientists used images from orbit to map the landing region's terrain types in a grid of 140 square quadrants, each about 0.9 mile (1.5 kilometers) wide. Curiosity entered its eighth quadrant this month. It departed one called Arlee, after a geological district in Montana, and drove into one called Windhoek, for a geological district in Namibia. Throughout the mission, the rover team has informally named Martian rocks, hills and other features for locations in the quadrant's namesake area on Earth. There's a new twist for the Windhoek Quadrant: scientists at the Geological Society of Namibia and at the Gobabeb Research and Training Center in Namibia have provided the rover team with a list of Namibian geological place names to use for features in this quadrant. The Windhoek theme was chosen for this sand-dune-bearing quadrant because studies of the Namib Desert have aided interpretation of dune and playa environments on Mars.

What distinguishes actual dunes from windblown ripples of sand or dust, like those found at several sites visited previously by Mars rovers, is that dunes form a downwind face steep enough for sand to slide down. The effect of wind on motion of individual particles in dunes has been studied extensively on Earth, a field pioneered by British military engineer Ralph Bagnold (1896-1990). Curiosity's campaign at the Martian dune field informally named for him will be the first in-place study of dune activity on a planet with lower gravity and less atmosphere.

Observations of the Bagnold Dunes with the Compact Reconnaissance Imaging Spectrometer on NASA's Mars Reconnaissance Orbiter indicate that mineral composition is not evenly distributed in the dunes. The same orbiter's High Resolution Imaging Science Experiment has documented movement of Bagnold Dunes.

"We will use Curiosity to learn whether the wind is actually sorting the minerals in the dunes by how the wind transports particles of different grain size," Ehlmann said.

As an example, the dunes contain olivine, a mineral in dark volcanic rock that is one of the first altered into other minerals by water. If the Bagnold campaign finds that other mineral grains are sorted away from heavier olivine-rich grains by the wind's effects on dune sands, that could help researchers evaluate to what extent low and high amounts of olivine in some ancient sandstones could be caused by wind-sorting rather than differences in alteration by water.

Ehlmann and Nathan Bridges of the Johns Hopkins University's Applied Physics Laboratory, Laurel, Maryland, lead the Curiosity team's planning for the dune campaign.

"These dunes have a different texture from dunes on Earth," Bridges said. "The ripples on them are much larger than ripples on top of dunes on Earth, and we don't know why. We have models based on the lower air pressure. It takes a higher wind speed to get a particle moving. But now we'll have the first opportunity to make detailed observations."

JPL, managed by Caltech for NASA, built Curiosity and manages the project for NASA's Science Mission Directorate in Washington. For more information about Curiosity, visit:

http://www.nasa.gov/msl
http://mars.jpl.nasa.gov/msl/

 http://spaceref.com/mars/curiosity-heads-toward-active-dunes.html

[BetaguyGZT]

Ahhhh yessss ... there's that smell again. Hot pockets and motor oil. AKA neurons operating at proper temperatures.

Mars and Titan. Two places on the "We gotta friggin' go there!" list. Above Enceladus and Europa, imho (but those two places NEED dedicated Lander Missions, without question).

Good grief, the science we can do on those four bodies ... yeah .... *drool*

[Draggendrop Veteran]

Ahhhh yessss ... there's that smell again. Hot pockets and motor oil. AKA neurons operating at proper temperatures.

Mars and Titan. Two places on the "We gotta friggin' go there!" list. Above Enceladus and Europa, imho (but those two places NEED dedicated Lander Missions, without question).

Good grief, the science we can do on those four bodies ... yeah .... *drool*

Have an Enceladus news package ready to post..real neat place.....

[BetaguyGZT]

Have an Enceladus news package ready to post..real neat place.....

That sexy, white-and-blue striped ball of hotness ... yeah. She's a pin-up girl, that one. Like Soyuz Launchers and Saturn-1B's. Centerfold material.

[Draggendrop Veteran]

This is the 6 month cruise that turned into 5 years due to a component failure....

Tiny thrusters to do heavy lifting as Japanese probe approaches Venus

 

Artist’s concept of Japan’s Akatsuki spacecraft at Venus. Credit: JAXA/Akihiro Ikeshita

Inside a month until its next chance to swing into orbit around Venus, Japan’s Akatsuki spacecraft has weathered unexpectedly “severe” conditions after missing an arrival opportunity in 2010, according to the mission’s project scientist.

The space probe accomplished its last targeting maneuver Oct. 11 to aim for its Dec. 7 arrival at Venus, and all systems are go for the encounter, said Takeshi Imamura, Akatsuki’s project scientist at JAXA’s Institute of Space and Astronautical Science.

Imamura said the Akatsuki spacecraft, named for the Japanese word for dawn, will zoom 541 kilometers, or 336 miles, above Venus for a 20-minute insertion burn using the probe’s secondary attitude control thrusters. Japanese ground controllers have programmed the probe to use the backup rocket jets after a faulty valve knocked out Akatsuki’s main engine during its first attempt to enter orbit around Venus in December 2010.

Four of the eight attitude control thrusters aboard Akatsuki will fire for 20 minutes and 33 seconds to slow the spacecraft down enough for Venus’ gravity to pull it into an egg-shaped orbit that skims above the planet’s cloud tops on the low end and ranges several hundred thousand miles in altitude at peak altitude.

The reaction control thrusters, originally designed to help point the spacecraft, were not rated for such a hefty propulsive maneuver.

“In the original plan, we used these RCS (thrusters) only for attitude control — mostly using these thrusters only for unloading angular momentum — so we did not expect such a long (burn),” Imamura said last month in a presentation to NASA’s Venus Exploration Analysis Group. “So yes … this kind of operation is rather dangerous, but in the previous (burns) already conducted, we have already tested 10 minutes of propulsion, so 20 minutes is not very long compared to the (maneuvers) we have already conducted.”

Akatsuki’s main engine, designed for 112 pounds of thrust, is unavailable after a failed burn during the mission’s first encounter with Venus five years ago. The engine cut off less than three minutes into a 12 minute burn, providing an insufficient impulse for the craft to be captured in orbit.

Engineers believe a salt formation in a check valve inside the spacecraft’s propulsion system restricted the flow of fuel to the main engine, starving it of fuel and creating an oxidizer-rich combustion condition, raising temperatures inside the engine before it failed.

The probe continued on in an orbit around the sun following the failed insertion maneuver in 2010, and ground controllers searched for a new way to steer Akatsuki into Venus’ orbit during its next flyby of the planet in 2015.

The ground team commanded Akatsuki to dump 65 kilograms, or 143 pounds, of unnecessary propellant to lighten the spacecraft, making it easier to maneuver with the secondary propulsion system, which does not require an oxidizer for its firings.

A series of course correction burns using the attitude control thrusters over the last five years has put Akatsuki on track for its Dec. 7 arrival opportunity. The maneuvers also demonstrated long duration burns, giving officials some confidence ahead of the make-or-break firing at Venus.

Akatsuki blasted off in May 2010 aboard a Japanese H-2A rocket, and the original flight plan called for a six-month cruise to Venus.

During its unexpected five-year sojourn, the probe passed closer to the sun than Akatsuki’s designers intended, spending months inside the orbit of Venus. The orbit forced the spacecraft to weather extreme temperatures that some officials worried would threaten the mission.

“The temperature condition was quite severe, especially when we passed through perihelion,” Imamura said. “We experienced unusually high temperatures repeatedly because of the short distance between the sun and Akatsuki at perihelion. The solar input was 37 perent larger than the nominal condition.”

The craft survived its last perihelion passage in August, and temperatures are now falling as it approaches Venus on the outbound leg of its orbit.

Akatsuki completed its last burn before getting to Venus in October, and tracking data supplied by NASA’s Deep Space Network show the probe is right on track for Venus.

While acknowledging the Dec. 7 maneuver is risky, Imamura said “we do not think of this operation as very dangerous.”

The smaller thrusters aboard Akatsuki generate just 5 pounds of thrust, a fraction of the power provided by the probe’s main engine. Even with four of the rocket jets operating — there are two sets of four pointing forward and aft from Akatwuki’s main body — the secondary thrusters do not have the energy to put the spacecraft into its originally planned orbit.

Instead, Akatsuki will go into a higher orbit than intended, and the change has some impact to the craft’s science mission, Imamura said.

Rather than taking about 30 hours to complete a lap around Venus — as was planned after the botched 2010 arrival — Akatsuki will complete one orbit every 15 days. Another maneuver in March will nudge Akatsuki closer to Venus, placing the probe in a nine-day orbit.

Imamura said three of Akatsuki’s five cameras were recently switched on for the first time in more than four years, and they appeared to be in good health. The other two cameras will be activated once the probe is in orbit at Venus.

Engineers plan to instruct Akatsuki to turn its cameras toward Venus immediately after the insertion burn in a bid to collect “contingency” imagery of the planet in case the maneuver fails.

 

 
Akatsuki captured these views of Venus in three wavelengths two days after the mission’s failed orbit insertion attempt 2010. Scientists plan to turn the probe’s cameras toward Venus immediately after the Dec. 7 arrival maneuver to record much closer views in case the burn fails. Credit: JAXA/ISAS

Scientists used the cameras to peer back at Venus from a distance of 600,000 kilometers — about 372,000 miles — after it missed the planet in 2010, revealing a thin sunlit crescent in infrared and ultraviolet.

Even if the upcoming bid to enter Venus’ orbit comes up short, scientists say Akatsuki will get a much closer look at the planet than possible in 2010.

If the arrival is successful, Akatsuki will become the only spacecraft currently operating at Venus. The European Space Agency’s Venus Express probe ended its mission there in late 2014.

Imamura said Japanese scientists have planned observations at Venus for at least two years after Akatsuki’s arrival.

“The orbit around Venus in the new plan will be a very long elliptical one,” Imamura said. “From far distances, we continually monitor the global-scale dynamics of the atmosphere and clouds, and of course, from close distances, we take close-up images of the atmosphere, the surface, and we also observe lightning and airglow when the spacecraft is in the shadow of Venus.”

Also named the Venus Climate Orbiter, Akatsuki is primarily designed to study the Venusian atmosphere.

The mission will observe climate and weather conditions on Venus with a suite of five cameras to look at low-altitude cloud patterns, chart the distribution of water vapor and carbon monoxide, and map the surface of Venus with a goal of finding active volcanoes. Thick clouds prevent visible cameras from seeing through Venus’ global clouds, but scientists say an infrared imager aboard Akatsuki can resolve the surface.

A long-wavelength infrared camera and an ultraviolet instrument aboard Akatsuki will study the super-rotating cloud structures in the upper atmosphere. The ultraviolet camera will also track sulfur dioxide, a precursor to cloud formation at Venus.

Researchers also plan to measure radio waves transmitted through the planet’s atmosphere to measure its profile.

Imamura said engineers have uploaded new software to Akatsuki to better see Venus from the spacecraft’s higher-than-planned orbit, reducing the data volume coming back to Earth to streamline the mission’s scientific return.

“By combining this information, we can model the three-dimensional structure of the atmosphere and the clouds,” Imamura said.

 http://spaceflightnow.com/2015/11/18/tiny-thrusters-to-do-heavy-lifting-as-japanese-probe-approaches-venus/

At least they are making the best of it.....long journey...for Venus.......

[Draggendrop Veteran]

Comparing Enceladus and Dione

 

Enceladus (L) and Dione (R)   NASA/JPL/SSI

Although Dione (near) and Enceladus (far) are composed of nearly the same materials, Enceladus has a considerably higher reflectivity than Dione. As a result, it appears brighter against the dark night sky.

The surface of Enceladus (313 miles or 504 kilometers across) endures a constant rain of ice grains from its south polar jets. As a result, its surface is more like fresh, bright, snow than Dione's (698 miles or 1123 kilometers across) older, weathered surface. As clean, fresh surfaces are left exposed in space, they slowly gather dust and radiation damage and darken in a process known as "space weathering."

This view looks toward the leading hemisphere of Enceladus. North on Enceladus is up and rotated 1 degree to the right. The image was taken in visible light with the Cassini spacecraft narrow-angle camera on Sept. 8, 2015.

The view was acquired at a distance of approximately 52,000 miles (83,000 kilometers) from Dione. Image scale is 1,600 feet (500 meters) per pixel. The distance from Enceladus was 228,000 miles (364,000 kilometers) for an image scale of 1.4 miles (2.2 kilometers) per pixel.

The Cassini mission is a cooperative project of NASA, ESA (the European Space Agency) and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colorado.

For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov orhttp://www.nasa.gov/cassini . The Cassini imaging team homepage is at http://ciclops.org .

 http://spaceref.com/saturn/comparing-enceladus-and-dione.html

-------------------------

bit of background data....

Enceladus

Enceladus (pronounced /ɛnˈsɛlədəs/) is the sixth-largest moon of Saturn. It is only 500 kilometers (310 mi) in diameter,^[3] about a tenth of that of Saturn's largest moon, Titan. Enceladus is mostly covered by fresh, clean ice, reflecting almost all the sunlight that strikes it and making its surface temperature at noon reach only −198 °C. Enceladus has a wide range of surface features, ranging from old, heavily cratered regions to young, tectonically deformed terrains that formed as recently as 100 million years ago, despite its small size.

Enceladus was discovered in 1789 by William Herschel,^[1][13][14] but little was known about it until the two Voyagerspacecraft passed nearby in the early 1980s.^[15] In 2005, the Cassini spacecraft started multiple close flybys of Enceladus, revealing its surface and environment in greater detail. In particular, Cassini discovered a water-rich plume venting from the south polar region of Enceladus.^[16] Cryovolcanoes near the south pole shoot geyser-like jets of water vapor, other volatiles, and solid material, including sodium chloride crystals and ice particles, into space, totaling approximately 200 kilograms (440 lb) per second.^[15][17][18] Over 100 geysers have been identified.^[19] Some of the water vapor falls back as "snow"; the rest escapes, and supplies most of the material making up Saturn's E ring.^[20][21] According to NASA scientists, the plumes at Enceladus are similar in composition to comets.^[22] In 2014, NASA reported that Cassini found evidence for a large south polar subsurface ocean of liquid water within Enceladus with a thickness of around 10 km.^[23][24][25]

These geyser observations, along with the finding of escaping internal heat and very few (if any) impact craters in the south polar region, show that Enceladus is geologically active today. Enceladus is, like many satellites in the extensive systems of giant planets, trapped in an orbital resonance. Its resonance with Dione excites its orbital eccentricity, which tidal forces damp, resulting in tidal heating of its interior, and offering a possible explanation for the geological activity.

https://en.wikipedia.org/wiki/Enceladus

---------------------------

The Moons of Saturn 

Saturn and its largest moons. Image credit: NASA/JPL/SSI

Saturn is well known for being a gas giant, and for its impressive ring system. But would it surprise you to know that this planet also has the second-most moons in the Solar System, second only to Jupiter? Yes, Saturn has at least 150 moons and moonlets in total, though only 53 of themhave been given official names.

Most of these moons are small, icy bodies that are little more than parts of its impressive ring system. In fact, 34 of the moons that have been named are less than 10 km in diameter while another 14 are 10 to 50 km in diameter. However, some of its inner and outer moons are among the largest and most dramatic in the Solar System, measuring between 250 and 5000 km in diameter and housing some of greatest mysteries in the Solar System.

More data at the link...
http://www.universetoday.com/15427/moons-of-saturn/

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 Deepest-Ever Dive Through Enceladus Plume Completed

 

NASA's Cassini spacecraft completed its deepest-ever dive through the icy plume of Enceladus on Oct. 28, 2015.

Credits: NASA/JPL-Caltech

 

NASA's Cassini spacecraft successfully completed its close flyby of Saturn's moon Enceladus today, passing 30 miles (49 kilometers) above the moon's south polar region at approximately 8:22 a.m. PDT (11:22 a.m. EDT). Mission controllers established two-way communication with the spacecraft this afternoon and expect it to begin transmitting data from the encounter this evening. Images are anticipated in the next 24 to 48 hours.

 

The Cassini-Huygens mission is a cooperative project of NASA, ESA (European Space Agency) and the Italian Space Agency. NASA's Jet Propulsion Laboratory in Pasadena, California, manages the mission for the agency's Science Mission Directorate in Washington. JPL is a division of the California Institute of Technology in Pasadena. The Cassini imaging operations center is based at the Space Science Institute in Boulder, Colorado.

 

 http://www.nasa.gov/feature/jpl/deepest-ever-dive-through-enceladus-plume-completed

----------------------------------------------

Closest Northern Views of Saturn's Moon Enceladus

 

 

NASA's Cassini spacecraft zoomed by Saturn's icy moon Enceladus on Oct. 14, 2015, capturing this stunning image of the moon's north pole.

Credits: NASA/JPL-Caltech/Space Science Institute

Full image and caption

 

 
 

NASA's Cassini spacecraft spied this tight trio of craters as it approached Saturn's icy moon Enceladus for a close flyby on Oct. 14, 2015.

Credits: NASA/JPL-Caltech/Space Science Institute

Full image and caption

 

NASA's Cassini spacecraft has begun returning its best-ever views of the northern extremes of Saturn's icy, ocean-bearing moon Enceladus. The spacecraft obtained the images during its Oct. 14 flyby, passing 1,142 miles (1,839 kilometers) above the moon's surface. Mission controllers say the spacecraft will continue transmitting images and other data from the encounter for the next several days.

 

Scientists expected the north polar region of Enceladus to be heavily cratered, based on low-resolution images from the Voyager mission, but the new high-resolution Cassini images show a landscape of stark contrasts. "The northern regions are crisscrossed by a spidery network of gossamer-thin cracks that slice through the craters," said Paul Helfenstein, a member of the Cassini imaging team at Cornell University, Ithaca, New York. "These thin cracks are ubiquitous on Enceladus, and now we see that they extend across the northern terrains as well."

 

In addition to the processed images, unprocessed, or "raw," images are posted on the Cassini mission website at:

 

http://saturn.jpl.nasa.gov/mission/flybys/enceladus20151014

 

Cassini's next encounter with Enceladus is planned for Oct. 28, when the spacecraft will come within 30 miles (49 kilometers) of the moon's south polar region. During the encounter, Cassini will make its deepest-ever dive through the moon's plume of icy spray, sampling the chemistry of the extraterrestrial ocean beneath the ice. Mission scientists are hopeful data from that flyby will provide evidence of how much hydrothermal activity is occurring in the moon's ocean, along with more detailed insights about the ocean's chemistry -- both of which relate to the potential habitability of Enceladus.

 

Cassini's final close Enceladus flyby will take place on Dec. 19, when the spacecraft will measure the amount of heat coming from the moon's interior. The flyby will be at an altitude of 3,106 miles (4,999 kilometers).

An online toolkit for all three final Enceladus flybys is available at:

 

http://solarsystem.nasa.gov/finalflybys

 

The Cassini-Huygens mission is a cooperative project of NASA, ESA (European Space Agency) and the Italian Space Agency. NASA's Jet Propulsion Laboratory in Pasadena, California, manages the mission for the agency's Science Mission Directorate in Washington. JPL is a division of the California Institute of Technology in Pasadena. The Cassini imaging operations center is based at the Space Science Institute in Boulder, Colorado.

 

For more information about Cassini, visit:

 

http://www.nasa.gov/cassini

http://saturn.jpl.nasa.gov

 

 http://www.nasa.gov/feature/jpl/closest-ever-views-of-saturns-moon-enceladus

------------------------------------

Icy Tendrils Reaching into Saturn Ring Traced to Their Source

 

 

This collage of Cassini spacecraft images and computer simulations shows how long, sinuous features from Enceladus can be modeled by tracing the trajectories of tiny, icy grains ejected from the moon's south polar geysers.

Credits: NASA/JPL-Caltech/SSI

Full image and caption

 

 

Long, sinuous, tendril-like structures seen in the vicinity of Saturn's icy moon Enceladus originate directly from geysers erupting from its surface, according to scientists studying images from NASA's Cassini spacecraft.

This result is published online today in a study in the Astronomical Journal, along with additional insights into the nature of the structures.

"We've been able to show that each unique tendril structure can be reproduced by particular sets of geysers on the moon's surface," said Colin Mitchell, a Cassini imaging team associate at the Space Science Institute in Boulder, Colorado, and lead author of the paper. Mitchell and colleagues used computer simulations to follow the trajectories of

ice grains ejected from individual geysers. The geysers, which were discovered by Cassini in 2005, are jets of tiny water ice particles, water vapor and simple organic compounds.

Under certain lighting conditions, Cassini's wide-view images showing icy material erupting from Enceladus reveal faint, finger-like features, dubbed "tendrils" by the imaging team. The tendrils reach into Saturn's E ring -- the ring in which Enceladus orbits -- extending tens of thousands of miles (or kilometers) away from the moon. Since the tendrils were discovered, scientists have thought they were the result of the moon's geysering activity and the means by which Enceladus supplies material to the E ring. But the ghostly features had never before been traced directly to geysers on the surface.

 

 

 
 

This graphic plots the source locations of geysers scientists have located on Enceladus' south polar terrain, with the 36 most active geyser sources marked and color coded by the behavior of the grains erupting from the geysers.

Credits: NASA/JPL-Caltech/SSI

 

 

Because the team was able to show that tendril structures of different shapes correspond to different sizes of geyser particles, the team was able to zero in on the sizes of the particles forming them. They found the tendrils are composed of particles with diameters no smaller than about a millionth of a meter (one meter is about 3 feet), a size consistent with the measurements of E-ring particles made by other Cassini instruments.

As the researchers examined images from different times and positions around Saturn, they also found that the detailed appearance of the tendrils changes over time. "It became clear to us that some features disappeared from one image to the next," said John Weiss, an imaging team associate at Saint Martin's University in Lacey, Washington, and an author on the paper.

The authors suspect that changes in the tendrils' appearance likely result from the cycle of tidal stresses -- squeezing and stretching of the moon as it orbits Saturn -- and its control of the widths of fractures from which the geysers erupt. The stronger the tidal stresses raised by Saturn at any point on the fractures, the wider the fracture opening and the greater the eruption of material. The authors will investigate in future work whether this theory explains the tendrils' changing appearance.

There is even more that can be extracted from the images, the scientists say. "As the supply lanes for Saturn's E ring, the tendrils give us a way to ascertain how much mass is leaving Enceladus and making its way into Saturn orbit," said Carolyn Porco, team leader for the imaging experiment and a coauthor on the paper. "So, another important step is to determine how much mass is involved, and thus estimate how much longer the moon's sub-surface ocean may last." An estimate of the lifetime of the ocean is important in understanding the evolution of Enceladus over long timescales.

Because of its significance to the investigation of possible extraterrestrial habitable zones, Enceladus is a major target of investigation for the final years of the Cassini mission. Many observations, including imaging of the plume and tendril features, and thermal observations of the surface of its south polar geyser basin, are planned during the next couple of years.

 

http://www.nasa.gov/jpl/cassini/icy-tendrils-reaching-into-saturn-ring-traced-to-their-source

-------------------------------------

Close View of Saturn's Moon Enceladus From Oct. 28 Flyby 

This unprocessed "raw" image of Saturn's icy, geologically active moon Enceladus was acquired by NASA's Cassini spacecraft during itsdramatic Oct. 28, 2015 flyby in which the probe passed about 30 miles (49 kilometers) above the moon's south polar region. The spacecraft will continue transmitting its data from the Enceladus encounter for the next several days. Cassini's next and final close Enceladus flyby will take place on Dec. 19, when the spacecraft will measure the amount of heat coming from the moon's interior.

Researchers will soon begin studying data from Cassini's gas analyzer and dust detector instruments, which directly sampled the moon's plume of gas and dust-sized icy particles during the flyby. Those analyses are likely to take several weeks, but should provide important insights about the composition of the global ocean beneath Enceladus' surface and any hydrothermal activity occurring on the ocean floor. The potential for such activity in this small ocean world has made Enceladus a prime target for future exploration in search of habitable environments in the solar system beyond Earth.

Image Credit: NASA/JPL-Caltech/Space Science Institute

 http://www.nasa.gov/image-feature/close-view-of-saturns-moon-enceladus-from-oct-28-flyby

------------------------------------------

Saturn's Geyser Moon Shines in Close Flyby Views

 

 

This unprocessed view of Saturn's moon Enceladus was acquired by NASA's Cassini spacecraft during a close flyby of the icy moon on Oct. 28, 2015.

Credits: NASA/JPL-Caltech/Space Science Institute

 

NASA's Cassini spacecraft has begun transmitting its latest images of Saturn's icy, geologically active moon Enceladus, acquired during the dramatic Oct. 28 flyby in which the probe passed about 30 miles (49 kilometers) above the moon's south polar region. The spacecraft will continue transmitting its data from the encounter for the next several days.

 

"Cassini's stunning images are providing us a quick look at Enceladus from this ultra-close flyby, but some of the most exciting science is yet to come," said Linda Spilker, the mission's project scientist at NASA's Jet Propulsion Laboratory in Pasadena, California.

 

Researchers will soon begin studying data from Cassini's gas analyzer and dust detector instruments, which directly sampled the moon's plume of gas and dust-sized icy particles during the flyby. Those analyses are likely to take several weeks, but should provide important insights about the composition of the global ocean beneath Enceladus' surface and any hydrothermal activity occurring on the ocean floor. The potential for such activity in this small ocean world has made Enceladus a prime target for future exploration in search of habitable environments in the solar system beyond Earth.

 

In addition to the processed images, unprocessed, or "raw," images appear on the Cassini mission website at:

 

http://saturn.jpl.nasa.gov/mission/flybys/enceladus20151028

 

Cassini's next and final close Enceladus flyby will take place on Dec. 19, when the spacecraft will measure the amount of heat coming from the moon's interior. The flyby will be at an altitude of 3,106 miles (4,999 kilometers).

 

http://www.nasa.gov/feature/jpl/saturns-geyser-moon-shines-in-close-flyby-views

 
 

Following a successful close flyby of Enceladus, NASA's Cassini spacecraft captured this artful composition of the icy moon with Saturn's rings beyond.

Credits: NASA/JPL-Caltech/Space Science Institute

 

 
 

During its closest ever dive past the active south polar region of Saturn's moon Enceladus,

Credits: NASA/JPL-Caltech/Space Science Institute

 

 

-----------------------------

Enceladus

 

This artist’s rendering showing a cutaway view into the interior of Saturn’s moon Enceladus. NASA’s Cassini spacecraft discovered the moon has a global ocean and likely hydrothermal activity. A plume of ice particles, water vapor and organic molecules sprays from fractures in the moon's south polar region.

 

This graphic is an update to a previously published version (see PIA19656) that did not show the ice and ocean layers to scale. The revised graphic more accurately represents scientists' current understanding of the thickness of the layers.

 

The Cassini mission is a cooperative project of NASA, ESA (the European Space Agency) and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL.

 

For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov and http://www.nasa.gov/cassini. The Cassini imaging team homepage is at http://ciclops.org.

Image Credit: NASA/JPL-Caltech

http://www.nasa.gov/image-feature/jpl/pia20013/enceladus

--------------------

NASA confirms there's a global subsurface ocean on Enceladus

 

We've known there is water on Enceladus for a while now, but NASA has just confirmed a more recent theory about the icy moon of Saturn: it has a subsurface ocean that spans the entire globe. The news comes just a handful of months after the agency discovered evidence of hydrothermal vents, which are believed to be integral to the formation of life here on Earth.

The confirmation was made using research from Cassini — a spacecraft that arrived at Saturn in 2004 and has spent the last decade studying the planet and its many moons. (It was launched in 1997.) The researchers used Cassini to measure the wobble in Enceladus' orbit of Saturn, something that "can only be accounted for if its outer ice shell is not frozen solid to its interior."

More data at the link...
http://www.theverge.com/2015/9/15/9333821/nasa-enceladus-subsurface-ocean

[BetaguyGZT]

Fantastic posts, DD. Got my Exogeology, Astrophysics and Aerospace Engineering juices flowing as only you (and DocM's) posts can. If I had been smarter in my post-Military life choices, I should have gone to College and pursued at least one of these careers. *sigh* The errors of youth ...

Anyway.

First comment, concerning the Japanese Probe with the failed Main Engine. Those RCS Thrusters (for those not familiar), while not meant to be used for extended periods of time like that, should work as well as any other source of propulsion so long as it has the Monopropellant supply enough to slow the probe down so Venus' gravity can capture it. RCS Thrusters aren't like an engine that you'd see lifting something off the ground -- they don't suffer the wear and tear or degredation like regular rocket engines. They're very simple, only a valve system and some sensors fed to the flight control software/hardware, and quite robust depending on the design.

They also run very cold -- one or two hundred degrees below freezing. In fact, the longer they run, the colder they get. Have you ever used a can of compressed air to blow out your computer, and after several seconds noticed that the can was quite cold, and after more use it was almost unbearably so? That's essentially what Monopropellant is. Different, of course, but the same general principles. It's stored as a liquid, but when the pressure gets low (as it escapes) it becomes a high-pressure gas, and that gas is what gives your thruster its' pushing ability. Now all you need is a directional valve, and some sensors to make sure your valve isn't leaking the propellant in the wrong exit chambers (making you go the wrong direction, essentially); or depending on the design of your thruster you don't have to worry about that problem ... it gets a little complicated to anyone who isn't savvy to this kind of thing.

But anyway, they aren't made for Orbital Insertion as such, but I don't see any real problem on the hardware with them doing it that way. Just the extreme use of their propellant, which will come back to haunt them 6-24 months (if not sooner) than they'd like. Of course, depending on their design (if they are the "valve" type), they could run into problems from the tendency for the propellant to corrode the gaskets ... eh. :shrug: Hope it works out for them.

Fun fact: If one were to look back at the Earth from Venus, we'd be magnitude -6.5 in the night sky at its' closest point to Venus (21 million miles, and 5 times brighter than Venus appears to us in our night sky!) -- a blazing, blue-white star and second in brightness only to the Sun. The Moon, ever nearby the Earth (but sometimes disappearing as it orbits it) would appear at its' brightest as magnitude -2.1 during those times, about the same brightness as Jupiter. And we'd always be a full disc to Venus, in a telescope.  Just looked that up a little while ago, and thought it was fascinating!

Second comment, concerning Enceladus: You gotta love this little Moons' moxy. It's got spirit. Anything that adds to the Ring System of Saturn to that degree and keeps on keepin' on is a winner in my book. That E Ring of Saturn is a true thing of beauty. 

Just lovely.  Enceladus made that. Even the "Pallene Ring" is part of the E Ring structure, so I'm pretty sure that name is gonna go out the window.

And a Global Subsurface Ocean, with the kinds of chemicals and molecules that are floating around the whole Saturnian system?! Yeah, there's gonna be some seriously interesting chemistry going on in that subsurface ocean, if they don't directly find lifeforms there. Likely near the places of Geothermal activity, like we have on Earth. And yes, they're going to be different in so many ways from what we're familiar with (or have even heard of) that it'll rewrite everything we thought we knew about like processes getting started.

I suspect that we'll find a similiar situation going on at Europa https://en.wikipedia.org/wiki/Europa_(moon) , and possibly Callisto https://en.wikipedia.org/wiki/Callisto_(moon) if the subsurface ocean there hasn't completely frozen up -- there's likely to be pockets of Geothermal activity keeping some sections thawed enough for interesting things to be happening.

Ganymede https://en.wikipedia.org/wiki/Ganymede_(moon) appears to have its' own magnetic field but it's quite deformed due to Jupiters quite immense and powerful field, so it's possible that the preliminary detection of that intrinsic field at Ganymede could have been due to a massive, deep, saltwater ocean of its' own.

So yeah, we need at least three Landers for Jupiters' Moons (one each) and I'm guessing at least two for Enceladus alone...

Your move, Humanity. Do we want to find out for sure?

[Draggendrop Veteran]

Yes, Europa is a neat place.....need to dig up news on this..

Fun fact: If one were to look back at the Earth from Venus, we'd be magnitude -6.5 in the night sky at its' closest point to Venus (21 million miles, and 5 times brighter than Venus appears to us in our night sky!) -- a blazing, blue-white star and second in brightness only to the Sun. The Moon, ever nearby the Earth (but sometimes disappearing as it orbits it) would appear at its' brightest as magnitude -2.1 during those times, about the same brightness as Jupiter. And we'd always be a full disc to Venus, in a telescope.  Just looked that up a little while ago, and thought it was fascinating!

BetaguyGZT recent post

Never thought of that....neat. I wonder if this situation is present, if on Mars, with Mars leading in orbit, as we look back on a sun drenched Earth...It would be quite the sight......

Recently, NASA decided to start another probe for Enceladus....sad part is, they are not going with the drill and submersible...hopefully they will change their minds...too many possibilities now..... 

[DocM]

All these worlds are yours, except Europa. Attempt no landing there. Use them together. Use them in peace.

[BetaguyGZT]

All these worlds are yours, except Europa. Attempt no landing there. Use them together. Use them in peace.

Love that series. But ....

... in the next book, Humans (with Dr. Floyd on board) made an emergency water landing on Europa, and discovered the perils of mixing differing bases of lifeforms -- notably, one of the Europan "Sharks" ate a Human carcass, and shortly afterward "vomited the contents of its' stomach, rolled over, and promptly died".

So yeah, mixing anything from Earth with anything else simply because it might "look tasty" is gonna be a bad experience -- and we need to remember that every moment we're "out there". Those lifeforms, even if they're just sitting there, even at the single-cell level, could be quite fatal to us -- and vice versa. There's no telling what can (and likely will) happen if Earth Biochemistry comes into contact with something ... foreign.

[BetaguyGZT]

Some more (theoretical) stuff I'm discovering about Ganymede -- very interesting stuff, in fact. Information from https://en.wikipedia.org/wiki/Ganymede_(moon)

Due to the presence of that magnetic field, the preliminary strength of which has been measured about 1.3 × 1013 T·m3 according to https://en.wikipedia.org/wiki/Ganymede_(moon)#Magnetosphere , Ganymede likely would have a significant atmosphere that it would have retained from its' formation up to the current day -- if not for the intense disruption of Jupiter's Magnetosphere at that location. Jupiter and Ganymede's magnetic fields "reconnect" at +/- 30° latitudes, causing such intense induction and coronal effects that any atmosphere would be stripped of its' protons (+ charge) and electrons (- charge) and carried off into space via the intense magnetic field lines. The remaining particles, neutrons, simply have nowhere to go; so they become accelerated and zip off in all directions. That's one hypothesis of what happens here.

The detection of an Oxygen atmosphere ( https://en.wikipedia.org/wiki/Ganymede_(moon)#Atmosphere_and_ionosphere ) is a direct result of this interaction. Evidence for a tenuous oxygen atmosphere (exosphere) on Ganymede, very similar to the one found on Europa, was found by the Hubble Space Telescope (HST) in 1995.[11][69] HST actually observed airglow of atomic oxygen in the far-ultraviolet at the wavelengths 130.4 nm and 135.6 nm. Such an airglow is excited when molecular oxygen is dissociated by electron impacts,[11] evidence of a significant neutral atmosphere composed predominantly of O2 molecules. The surface number density probably lies in the 1.2 × 108–7 × 108 cm−3 range, corresponding to the surface pressure of 0.2–1.2 µPa (0.0002 millibar to 0.002 millibar). It's quite tenuous, and any Probe landing there would not need to account for it at all. To put that into perspective, the pressure on Pluto and Mars is higher by a factor of nearly 1,000. IT's simply *there* due to the interaction of the two clashing magnetic fields, and is molecular oxygen and (most probably) ozone as the induction currents come into direct contact with the primarily water-ice surface.

What does this mean for a subsurface (likely salt-enriched) ocean? Any life occurring there would be subject to these intense and violent "induction currents" that likely permeate the Moon. Ganymede, if it were not a Moon, would be a bonafide planet in its' own right (being the largest Moon in the Solar System); and if not for the severe disruption from nearby Jupiter (even at an average of 1,070,400 km or 665,000 mi) Ganymede could be a smaller analogue of Earth at 5,268 km (3,273 mi) wide, with 45% the mass of Mercury (probably due to the subsurface ocean) and 2.741 km/s escape velocity (that's 2,741 m/sec for KSP fans) if placed in Earth's orbit and inclination. It's an interesting place.

  

(Images courtesy of Wikipedia / Wikimedia)

https://upload.wikimedia.org/wikipedia/commons/8/8a/Ganymede-JupiterMoon-GeologicMap-SIM3237-20140211.png For a larger view of the Ganymede Geology thumbnail above. It's very interesting.

 

Edited November 20, 2015 by BetaguyGZT
Added information about atmosphere.

[Draggendrop Veteran]

That ocean is huge...much larger than Enceladus. Those discharges and magnetic re-connections would look great if we could capture an image in a different spectrum. This energy could possibly be "used" by a "lifeform" if present, stranger things are possible (reverse process of an electric eel, electrical to chemical). We will have to look at this sometime....for now.......Doc has me spooked on Europa...not going to play there....

[BetaguyGZT]

Edited the above with info about the quite tenuous atmosphere on Ganymede.  I'm in Research Mode tonight!

[Draggendrop Veteran]

Edited the above with info about the quite tenuous atmosphere on Ganymede.  I'm in Research Mode tonight!

and do post.......

[BetaguyGZT]

and do post.......

You asked for it.  It's interesting to me that Titan, if we include the quite substantial and wide-ranging atmosphere, would technically be the largest Moon in the Solar System. By nearly 10%. Ganymede enjoys no such advantage; however, if it had been able to hang on to its' atmosphere, depending primarily on distance from Jupiter (more = better), Ganymede would be a much different place.

Titan's atmosphere extends quite a way up, nearly 600 km from the surface. It's massive -- more so than Earth's, in fact.

Yeah ....  Could Ganymede match this with a (likely, according to the chemistry we're seeing there) high-Oxygen and (likely) Sulphur? Maybe. Could we exist in such an atmosphere? No way -- the resulting atmosphere would be Sulphur Dioxide -- pretty much acid. We'd literally melt where we stood. Now add salt water, which will incorporate that nasty Sulphur Dioxide into liquid form. Now we get a condition where we'd be literally unable to land a probe anywhere on that Moon, land or sea. Nothing would last long. Nope, it would be Orbiters only, like Venus.

Does it make for some interesting chemistry? Nah. It's a corrosive. No biology could deal with it, not even Sulphur-based. Nothing can get a start before that SO2 is destroying it.

Ganymede would be doomed to be an interesting place to look at. Like Venus.

[Draggendrop Veteran]

So basically....we have a planetary battery......

[BetaguyGZT]

Essentially, that's what Ganymede is.

[Draggendrop Veteran]

These are still neat places to research and monitor news on....who knows.....everything has a useful purpose.....we just don't know yet. Cassini has done some wild research...it went pretty deep into Titan's atmosphere, from the look of it.......one place of note for resources later...is Iapetus and that neat equatorial mountain ridge circling the planetoid......

[BetaguyGZT]

These are still neat places to research and monitor news on....who knows.....everything has a useful purpose.....we just don't know yet. Cassini has done some wild research...it went pretty deep into Titan's atmosphere, from the look of it.......one place of note for resources later...is Iapetus and that neat equatorial mountain ridge circling the planetoid......

As long as we don't count the "shenanigans" about it being some sort of "Death Star remnant" and such. Sheesh, that made me literally roll my eyes when I heard that the first time.

We need another series of long-term missions like Cassini to Jupiter (three Landers), Saturn (with at four Landers this time), Uranus (possibly two Landers) and Neptune (a Lander for Triton). If we want to generate the next two decades worth of science, we need to start planning those missions now and get those missions launched yesterday.

Even if they're just uprated or (they'd have to be) upsized Cassini models with updated technology and designed to handle the additional Landers, we need to get moving on that now. I'd love to see that happen, but obviously the financial climate isn't conducive to that.

[Draggendrop Veteran]

It would be nice, in the future, if commercial interests could be involved in such a way as resources or the selling of high quality data to NASA to offset the costs of the operation. We could use more involvement in the future...to get more research done at a faster pace....so many places to see...so many places to do work....

Maybe even a competition for economical and high tech landers with launch costs subsidized...may be cheaper....