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NASA Spacecraft Investigate Clues in Radiation Belts

 

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High above Earth, two giant rings of energetic particles trapped by the planet’s magnetic field create a dynamic and harsh environment that holds many mysteries — and can affect spacecraft traveling around Earth. NASA’s Van Allen Probes act as space detectives, to help study the complex particle interactions that occur in these rings, known as the Van Allen radiation belts. Recently, the spacecraft were in just the right place, at just the right time, to catch an event caused by the fallout of a geomagnetic storm as it happened. They spotted a sudden rise in particles zooming in from the far side of the planet, improving our understanding of how particles travel in near-Earth space.

 

The two twin Van Allen Probe spacecraft orbit one behind the other, investigating clues in a way a single spacecraft never could. On one typical day, as the first instrument traveled around Earth, it spotted nothing unusual, but the second, following just an hour later, observed an increase in oxygen particles speeding around Earth’s dayside — the side nearest the sun. Where did these particles come from? How had they become so energized?

 

Scientists scoured the clues to figure out what was happening. With the help of computer models, they deduced that the particles had originated on the night side of Earth before being energized and accelerated through interactions with Earth’s magnetic field. As the particles journeyed around Earth, the lighter hydrogen particles were lost in collisions with the atmosphere, leaving an oxygen-rich plasma. The findings were presented in a recent paper in Geophysical Review Letters.

 

The unique double observations of the Van Allen Probes help untangle the complex workings of Earth’s magnetic environment. Such information has provided the very first view of these harsh belts from the inside — and it helps us better protect satellites and astronauts traveling through the region.

https://www.nasa.gov/feature/goddard/2017/nasa-spacecraft-investigate-clues-in-radiation-belts

 

 

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The twin Van Allen Probes orbit one behind the other, investigating clues in a way a single spacecraft never could. In this model, the trailing spacecraft saw an increase in injected oxygen particles (blue), which was unobserved by the first. The increase in particles was due to a geomagnetic storm front that moved across the path of the orbit after the first spacecraft passed.
Credits: NASA’s Goddard Space Flight Center/Mike Henderson/Joy Ng, Producer

 

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Comet That Took a Century to Confirm Passes by Earth

 

On April 1, 2017, comet 41P will pass closer than it normally does to Earth, giving observers with binoculars or a telescope a special viewing opportunity. Comet hunters in the Northern Hemisphere should look for it near the constellations Draco and Ursa Major, which the Big Dipper is part of.

 

Whether a comet will put on a good show for observers is notoriously difficult to predict, but 41P has a history of outbursts, and put on quite a display in 1973. If the comet experiences similar outbursts this time, there’s a chance it could become bright enough to see with the naked eye. The comet is expected to reach perihelion, or its closest approach to the sun, on April 12.

 

Officially named 41P/Tuttle-Giacobini-Kresák to honor its three discoverers, the comet is being playfully called the April Fool’s Day comet on this pass. Discovery credit goes first to Horace Tuttle, who spotted the comet in 1858. According to the Cometography website, 41P was recognized at the time as a periodic comet — one that orbits the sun — but astronomers initially were uncertain how long the comet needed to make the trip. The comet was rediscovered in 1907 by Michael Giacobini but not immediately linked to the object seen in 1858.

 

Later, the astronomer Andrew Crommelin determined that the two observations had been of the same object and predicted that the comet would return in 1928 and 1934, according to the Cometography entry for the comet. However, the object was not seen then and was considered lost. In 1951, L’ubor Kresák discovered it again and tied it to the earlier observations.

 

A member of the Jupiter family of comets, 41P makes a trip around the sun every 5.4 years, coming relatively close to Earth on some of those trips. On this approach, the comet will pass our planet at a distance of about 13 million miles (0.14 astronomical units), or about 55 times the distance from Earth to the moon. This is the comet’s closest approach to Earth in more than 50 years and perhaps more than a century.

 

For scientists, 41P’s visit is an opportunity to fill in details about the comet’s composition, coma and nucleus.

 

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More at NASA

 


 

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NASA Unveils New Searchable Video, Audio and Imagery Library for the Public

 

NASA officially has launched a new resource to help the public search and download out-of-this-world images, videos and audio files by keyword and metadata searches from NASA.gov. The NASA Image and Video Library website consolidates imagery spread across more than 60 collections into one searchable location. 

 

https://images.nasa.gov

 

NASA Image and Video Library allows users to search, discover and download a treasure trove of more than 140,000 NASA images, videos and audio files from across the agency’s many missions in aeronautics, astrophysics, Earth science, human spaceflight, and more. Users now can embed content in their own sites and choose from multiple resolutions to download. The website also displays the metadata associated with images. 

 

Users can browse the agency’s most recently uploaded files, as well as discover historic and the most popularly searched images, audio files and videos. Other features include:

 

  • Automatically scales the interface for mobile phones and tablets
  • Displays the EXIF/camera data that includes exposure, lens used, and other information, when available from the original image
  • Allows for easy public access to high resolution files
  • All video includes a downloadable caption file

 

NASA Image and Video Library’s Application Programmers Interface (API) allows automation of imagery uploads for NASA, and gives members of the public the ability to embed content in their own sites and applications. This public site runs on NASA’s cloud native “infrastructure-as-a-code” technology enabling on-demand use in the cloud.

 

The library is not comprehensive, but rather provides the best of what NASA makes publicly available from a single point of presence on the web. Additionally, it is a living website, where new and archival images, video and audio files continually will be added.

NASA

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NASA's Cassini spacecraft, in orbit around Saturn since 2004, is about to begin the final chapter of its remarkable story. On Wednesday, April 26, the spacecraft will make the first in a series of dives through the 1,500-mile-wide (2,400-kilometer) gap between Saturn and its rings as part of the mission’s grand finale.

 

"No spacecraft has ever gone through the unique region that we'll attempt to boldly cross 22 times," said Thomas Zurbuchen, associate administrator for the Science Mission Directorate at NASA Headquarters in Washington. "What we learn from Cassini’s daring final orbits will further our understanding of how giant planets, and planetary systems everywhere, form and evolve. This is truly discovery in action to the very end."

 

During its time at Saturn, Cassini has made numerous dramatic discoveries, including a global ocean that showed indications of hydrothermal activity within the icy moon Enceladus, and liquid methane seas on its moon Titan.

 

Now 20 years since launching from Earth, and after 13 years orbiting the ringed planet, Cassini is running low on fuel. In 2010, NASA decided to end the mission with a purposeful plunge into Saturn this year in order to protect and preserve the planet's moons for future exploration -- especially the potentially habitable Enceladus. 

 

But the beginning of the end for Cassini is, in many ways, like a whole new mission. Using expertise gained over the mission's many years, Cassini engineers designed a flight plan that will maximize the scientific value of sending the spacecraft toward its fateful plunge into the planet on Sept. 15. As it ticks off its terminal orbits during the next five months, the mission will rack up an impressive list of scientific achievements.

 

But the beginning of the end for Cassini is, in many ways, like a whole new mission. Using expertise gained over the mission's many years, Cassini engineers designed a flight plan that will maximize the scientific value of sending the spacecraft toward its fateful plunge into the planet on Sept. 15. As it ticks off its terminal orbits during the next five months, the mission will rack up an impressive list of scientific achievements.

 

"This planned conclusion for Cassini's journey was far and away the preferred choice for the mission's scientists," said Linda Spilker, Cassini project scientist at NASA’s Jet Propulsion Laboratory in Pasadena, California. "Cassini will make some of its most extraordinary observations at the end of its long life."

 

The mission team hopes to gain powerful insights into the planet's internal structure and the origins of the rings, obtain the first-ever sampling of Saturn's atmosphere and particles coming from the main rings, and capture the closest-ever views of Saturn's clouds and inner rings. The team currently is making final checks on the list of commands the robotic probe will follow to carry out its science observations, called a sequence, as it begins the finale. That sequence is scheduled to be uploaded to the spacecraft on Tuesday, April 11.

 

Cassini will transition to its grand finale orbits, with a last close flyby of Saturn's giant moon Titan, on Saturday, April 22. As it has many times over the course of the mission, Titan's gravity will bend Cassini's flight path. Cassini's orbit then will shrink so that instead of making its closest approach to Saturn just outside the rings, it will begin passing between the planet and the inner edge of its rings.

 

"Based on our best models, we expect the gap to be clear of particles large enough to damage the spacecraft. But we're also being cautious by using our large antenna as a shield on the first pass, as we determine whether it's safe to expose the science instruments to that environment on future passes," said Earl Maize, Cassini project manager at JPL. "Certainly there are some unknowns, but that's one of the reasons we're doing this kind of daring exploration at the end of the mission."

 

In mid-September, following a distant encounter with Titan, the spacecraft's path will be bent so that it dives into the planet. When Cassini makes its final plunge into Saturn's atmosphere on Sept. 15, it will send data from several instruments – most notably, data on the atmosphere's composition -- until its signal is lost.

 

"Cassini's grand finale is so much more than a final plunge," said Spilker. "It's a thrilling final chapter for our intrepid spacecraft, and so scientifically rich that it was the clear and obvious choice for how to end the mission."

 

Resources related to Cassini's grand finale, including images and video, are available at: http://saturn.jpl.nasa.gov/grandfinale

- NASA's Jet Propulsion Laboratory 

 

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End of Mission: 15 Sep 2017

 

:(

 

 

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This image, taken by the JunoCam imager on NASA’s Juno spacecraft, highlights a feature on Jupiter where multiple atmospheric conditions appear to collide.

 

This publicly selected target is called “STB Spectre.” The ghostly bluish streak across the right half of the image is a long-lived storm, one of the few structures perceptible in these whitened latitudes where the south temperate belt of Jupiter would normally be. The egg-shaped spot on the lower left is where incoming small dark spots make a hairpin turn.

 

The image was taken on March 27, 2017, at 2:06 a.m. PDT (5:06 a.m. EDT), as the Juno spacecraft performed a close flyby of Jupiter. When the image was taken, the spacecraft was 7,900 miles (12,700 kilometers) from the planet.

 

The image was processed by Roman Tkachenko, and the description is from John Rogers, the citizen scientist who identified the point of interest. 

 

JunoCam's raw images are available for the public to peruse and process into image products at: www.missionjuno.swri.edu/junocam  

 

More information about Juno is at: http://www.nasa.gov/juno and http://missionjuno.swri.edu  

Credits: NASA/JPL-Caltech/SwRI/MSSS/ Roman Tkachenko

 

NASA

 

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Asteroid to Fly Safely Past Earth on April 19

A relatively large near-Earth asteroid discovered nearly three years ago will fly safely past Earth on April 19 at a distance of about 1.1 million miles (1.8 million kilometers), or about 4.6 times the distance from Earth to the moon. Although there is no possibility for the asteroid to collide with our planet, this will be a very close approach for an asteroid of this size.

 

The asteroid, known as 2014 JO25, was discovered in May 2014 by astronomers at the Catalina Sky Survey near Tucson, Arizona -- a project of NASA's NEO Observations Program in collaboration with the University of Arizona. (An NEO is a near-Earth object). Contemporary measurements by NASA's NEOWISE mission indicate that the asteroid is roughly 2,000 feet (650 meters) in size, and that its surface is about twice as reflective as that of the moon. At this time very little else is known about the object’s physical properties, even though its trajectory is well known.

 

The asteroid will approach Earth from the direction of the sun and will become visible in the night sky after April 19. It is predicted to brighten to about magnitude 11, when it could be visible in small optical telescopes for one or two nights before it fades as the distance from Earth rapidly increases.

 

Small asteroids pass within this distance of Earth several times each week, but this upcoming close approach is the closest by any known asteroid of this size, or larger, since asteroid Toutatis, a 3.1-mile (five-kilometer) asteroid, which approached within about four lunar distances in September 2004. The next known encounter of an asteroid of comparable size will occur in 2027 when the half-mile-wide (800-meter-wide) asteroid 1999 AN10 will fly by at one lunar distance, about 236,000 miles (380,000 kilometers).

 

The April 19 encounter provides an outstanding opportunity to study this asteroid, and astronomers plan to observe it with telescopes around the world to learn as much about it as possible. Radar observations are planned at NASA's Goldstone Solar System Radar in California and the National Science Foundation’s Arecibo Observatory in Puerto Rico, and the resulting radar images could reveal surface details as small as a few meters.

 

The encounter on April 19 is the closest this asteroid has come to Earth for at least the last 400 years and will be its closest approach for at least the next 500 years.

 

Also on April 19, the comet PanSTARRS (C/2015 ER61) will make its closest approach to Earth, at a very safe distance of 109 million miles (175 million kilometers). A faint fuzzball in the sky when it was discovered in 2015 by the Pan-STARRS NEO survey team using a telescope on the summit of Haleakala, Hawaii, the comet has brightened considerably due to a recent outburst and is now visible in the dawn sky with binoculars or a small telescope.

 

JPL manages and operates NASA's Deep Space Network, including the Goldstone Solar System Radar, and hosts the Center for Near-Earth Object Studies for NASA's Near-Earth Object Observations Program, an element of the Planetary Defense Coordination Office within the agency's Science Mission Directorate.

 

NASA

 

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A Whole New Jupiter: First Science Results from NASA’s Juno Mission

 

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This image shows Jupiter’s south pole, as seen by NASA’s Juno spacecraft from an altitude of 32,000 miles (52,000 kilometers). The oval features are cyclones, up to 600 miles (1,000 kilometers) in diameter. Multiple images taken with the JunoCam instrument on three separate orbits were combined to show all areas in daylight, enhanced color, and stereographic projection.

Credits: NASA/JPL-Caltech/SwRI/MSSS/Betsy Asher Hall/Gervasio Robles

 

Early science results from NASA’s Juno mission to Jupiter portray the largest planet in our solar system as a complex, gigantic, turbulent world, with Earth-sized polar cyclones, plunging storm systems that travel deep into the heart of the gas giant, and a mammoth, lumpy magnetic field that may indicate it was generated closer to the planet’s surface than previously thought.

 

“We are excited to share these early discoveries, which help us better understand what makes Jupiter so fascinating,” said Diane Brown, Juno program executive at NASA Headquarters in Washington. "It was a long trip to get to Jupiter, but these first results already demonstrate it was well worth the journey.”

 

Juno launched on Aug. 5, 2011, entering Jupiter’s orbit on July 4, 2016. The findings from the first data-collection pass, which flew within about 2,600 miles (4,200 kilometers) of Jupiter's swirling cloud tops on Aug. 27, are being published this week in two papers in the journal Science, as well as 44 papers in Geophysical Research Letters.

 

“We knew, going in, that Jupiter would throw us some curves,” said Scott Bolton, Juno principal investigator from the Southwest Research Institute in San Antonio. “But now that we are here we are finding that Jupiter can throw the heat, as well as knuckleballs and sliders. There is so much going on here that we didn’t expect that we have had to take a step back and begin to rethink of this as a whole new Jupiter.”

 

Among the findings that challenge assumptions are those provided by Juno’s imager, JunoCam. The images show both of Jupiter's poles are covered in Earth-sized swirling storms that are densely clustered and rubbing together.

 

“We're puzzled as to how they could be formed, how stable the configuration is, and why Jupiter’s north pole doesn't look like the south pole,” said Bolton. “We're questioning whether this is a dynamic system, and are we seeing just one stage, and over the next year, we're going to watch it disappear, or is this a stable configuration and these storms are circulating around one another?”

 

Another surprise comes from Juno’s Microwave Radiometer (MWR), which samples the thermal microwave radiation from Jupiter’s atmosphere, from the top of the ammonia clouds to deep within its atmosphere. The MWR data indicates that Jupiter’s iconic belts and zones are mysterious, with the belt near the equator penetrating all the way down, while the belts and zones at other latitudes seem to evolve to other structures. The data suggest the ammonia is quite variable and continues to increase as far down as we can see with MWR, which is a few hundred miles or kilometers. 

 

Prior to the Juno mission, it was known that Jupiter had the most intense magnetic field in the solar system. Measurements of the massive planet’s magnetosphere, from Juno’s magnetometer investigation (MAG), indicate that Jupiter’s magnetic field is even stronger than models expected, and more irregular in shape. MAG data indicates the magnetic field greatly exceeded expectations at 7.766 Gauss, about 10 times stronger than the strongest magnetic field found on Earth.

 

“Juno is giving us a view of the magnetic field close to Jupiter that we’ve never had before,” said Jack Connerney, Juno deputy principal investigator and the lead for the mission’s magnetic field investigation at NASA's Goddard Space Flight Center in Greenbelt, Maryland. “Already we see that the magnetic field looks lumpy: it is stronger in some places and weaker in others. This uneven distribution suggests that the field might be generated by dynamo action closer to the surface, above the layer of metallic hydrogen. Every flyby we execute gets us closer to determining where and how Jupiter’s dynamo works.”

 

Juno also is designed to study the polar magnetosphere and the origin of Jupiter's powerful auroras—its northern and southern lights. These auroral emissions are caused by particles that pick up energy, slamming into atmospheric molecules. Juno’s initial observations indicate that the process seems to work differently at Jupiter than at Earth.

 

Juno is in a polar orbit around Jupiter, and the majority of each orbit is spent well away from the gas giant. But, once every 53 days, its trajectory approaches Jupiter from above its north pole, where it begins a two-hour transit (from pole to pole) flying north to south with its eight science instruments collecting data and its JunoCam public outreach camera snapping pictures. The download of six megabytes of data collected during the transit can take 1.5 days.

 

“Every 53 days, we go screaming by Jupiter, get doused by a fire hose of Jovian science, and there is always something new,” said Bolton. “On our next flyby on July 11, we will fly directly over one of the most iconic features in the entire solar system -- one that every school kid knows -- Jupiter’s Great Red Spot. If anybody is going to get to the bottom of what is going on below those mammoth swirling crimson cloud tops, it’s Juno and her cloud-piercing science instruments.”

 

NASA's Jet Propulsion Laboratory in Pasadena, California, manages the Juno mission for NASA. The principal investigator is Scott Bolton of the Southwest Research Institute in San Antonio. The Juno mission is part of the New Frontiers Program managed by NASA's Marshall Space Flight Center in Huntsville, Alabama, for the agency’s Science Mission Directorate. Lockheed Martin Space Systems, in Denver, built the spacecraft.

 

More information on the Juno mission is available at:

https://www.nasa.gov/juno

NASA

 

Below is the article mentioned in the NASA press release.

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Jupiter’s interior and deep atmosphere: The initial pole-to-pole passes with the Juno spacecraft

 

Abstract

On 27 August 2016, the Juno spacecraft acquired science observations of Jupiter, passing less than 5000 kilometers above the equatorial cloud tops. Images of Jupiter’s poles show a chaotic scene, unlike Saturn’s poles. Microwave sounding reveals weather features at pressures deeper than 100 bars, dominated by an ammonia-rich, narrow low-latitude plume resembling a deeper, wider version of Earth’s Hadley cell. Near-infrared mapping reveals the relative humidity within prominent downwelling regions. Juno’s measured gravity field differs substantially from the last available estimate and is one order of magnitude more precise. This has implications for the distribution of heavy elements in the interior, including the existence and mass of Jupiter’s core. The observed magnetic field exhibits smaller spatial variations than expected, indicative of a rich harmonic content.

Science Mag

 

...and the other one mentioned in the NASA press release.

 

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Accelerated flows at Jupiter's magnetopause: Evidence for magnetic reconnection along the dawn flank

 

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We report on plasma and magnetic field observations from Juno's Jovian Auroral Distributions Experiment and Magnetic Field Investigation at 18 magnetopause crossings when the spacecraft was located at ~6 h magnetic local time and 73–114 Jovian radii from Jupiter. Several crossings showed evidence of plasma energization, accelerated ion flows, and large magnetic shear angles, each representing a signature of magnetic reconnection. These signatures were observed for times when the magnetosphere was in both compressed and expanded states. We compared the flow change magnitudes to a simplified Walén relation and found ~60% of the events to be 110% or less of the predicted values. Close examination of two magnetopause encounters revealed characteristics of a rotational discontinuity and an open magnetopause. These observations provide compelling evidence that magnetic reconnection can occur at Jupiter's dawn magnetopause and should be incorporated into theories of solar wind coupling and outer magnetosphere dynamics at Jupiter.

AGU Publications (behind a paywall)

 

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Sequence of Juno Spacecraft's Close Approach to Jupiter

 

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This sequence of enhanced-color images shows how quickly the viewing geometry changes for NASA’s Juno spacecraft as it swoops by Jupiter. The images were obtained by JunoCam.

 

Once every 53 days the Juno spacecraft swings close to Jupiter, speeding over its clouds. In just two hours, the spacecraft travels from a perch over Jupiter’s north pole through its closest approach (perijove), then passes over the south pole on its way back out. This sequence shows 14 enhanced-color images.

 

The first image on the left shows the entire half-lit globe of Jupiter, with the north pole approximately in the center. As the spacecraft gets closer to Jupiter, the horizon moves in and the range of visible latitudes shrinks. The third and fourth images in this sequence show the north polar region rotating away from our view while a band of wavy clouds at northern mid-latitudes comes into view. By the fifth image of the sequence the band of turbulent clouds is nicely centered in the image. The seventh and eighth images were taken just before the spacecraft was at its closest point to Jupiter, near Jupiter’s equator. Even though these two pictures were taken just four minutes apart, the view is changing quickly.

 

As the spacecraft crossed into the southern hemisphere, the bright “south tropical zone” dominates the ninth, 10th and 11th images. The white ovals in a feature nicknamed Jupiter’s “String of Pearls” are visible in the 12th and 13th images. In the 14th image Juno views Jupiter’s south poles.

NASA (which includes a higher resolution of the above image)

 

 

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Cassini Finds Saturn Moon May Have Tipped Over

 

Saturn's icy, ocean-bearing moon Enceladus may have tipped over in the distant past, according to recent research from NASA's Cassini mission. Researchers with the mission found evidence that the moon's spin axis -- the line through the north and south poles -- has reoriented, possibly due to a collision with a smaller body, such as an asteroid.

 

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Examining the moon's features, the team showed that Enceladus appears to have tipped away from its original axis by about 55 degrees -- more than halfway toward rolling completely onto its side. "We found a chain of low areas, or basins, that trace a belt across the moon's surface that we believe are the fossil remnants of an earlier, previous equator and poles," said Radwan Tajeddine, a Cassini imaging team associate at Cornell University, Ithaca, New York, and lead author of the paper.

 

The area around the icy moon's current south pole is a geologically active region where long, linear fractures referred to as tiger stripes slice across the surface. Tajeddine and colleagues speculate that an asteroid may have struck the region in the past when it was closer to the equator. "The geological activity in this terrain is unlikely to have been initiated by internal processes," he said. "We think that, in order to drive such a large reorientation of the moon, it's possible that an impact was behind the formation of this anomalous terrain."

 

In 2005, Cassini discovered that jets of water vapor and icy particles spray from the tiger stripe fractures -- evidence that an underground ocean is venting directly into space from beneath the active south polar terrain.

 

Whether it was caused by an impact or some other process, Tajeddine and colleagues think the disruption and creation of the tiger-stripe terrain caused some of Enceladus' mass to be redistributed, making the moon's rotation unsteady and wobbly. The rotation would have eventually stabilized, likely taking more than a million years. By the time the rotation settled down, the north-south axis would have reoriented to pass through different points on the surface -- a mechanism researchers call "true polar wander."

 

The polar wander idea helps to explain why Enceladus' modern-day north and south poles appear quite different. The south is active and geologically young, while the north is covered in craters and appears much older. The moon's original poles would have looked more alike before the event that caused Enceladus to tip over and relocate the disrupted tiger-stripe terrain to the moon's south polar region.

 

The results were published in the online edition of the journal Icarus on April 30, 2017.

 

The Cassini-Huygens mission is a cooperative project of NASA, ESA (European Space Agency) and the Italian Space Agency. NASA's Jet Propulsion Laboratory, a division of Caltech in Pasadena, California, manages the mission for NASA's Science Mission Directorate, Washington. JPL designed, developed and assembled the Cassini orbiter.

 

More information about Cassini:

https://www.nasa.gov/cassini

https://saturn.jpl.nasa.gov

NASA

 


 

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High-Silica 'Halos' Shed Light on Wet Ancient Mars

 

Pale "halos" around fractures in bedrock analyzed by NASA's Curiosity Mars rover contain copious silica, indicating that ancient Mars had liquid water for a long time.

 

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"The concentration of silica is very high at the centerlines of these halos," said Jens Frydenvang, a rover-team scientist at Los Alamos National Laboratory in New Mexico, and the University of Copenhagen in Denmark. "What we’re seeing is that silica appears to have migrated between very old sedimentary bedrock and into younger overlying rocks."

 

Frydenvang is the lead author of a report about these findings published in Geophysical Research Letters.

 

NASA landed Curiosity on Mars in 2012 with a goal to determine whether Mars ever offered environmental conditions favorable for microbial life. The mission "has been very successful in showing that Gale Crater once held a lake with water that we would even have been able to drink from, but we still don’t know how long this habitable environment endured," he said. "What this finding tells us is that, even when the lake eventually evaporated, substantial amounts of groundwater were present for longer than we previously thought -- further expanding the window for when life might have existed on Mars."

 

For more information about the newly published report, visit: http://bit.ly/2r8dyOF

 

The halos were first analyzed in 2015 with Curiosity's science-instrument payload, including the laser-shooting Chemistry and Camera (ChemCam) instrument, which was developed at Los Alamos National Laboratory in conjunction with the French space agency. The rover has subsequently explored higher and younger layers of lower Mount Sharp, investigating how ancient environmental conditions changed.

 

NASA's two active Mars rovers and three Mars orbiters are all part of ambitious robotic exploration to understand Mars, which helps lead the way for sending humans to Mars in the 2030s. The Curiosity mission is managed by NASA's Jet Propulsion Laboratory, a division of Caltech in Pasadena, California, for NASA's Science Mission Directorate, Washington.

 

For more about Curiosity, visit:

http://www.nasa.gov/curiosity

NASA

 

 

 

First image ever of Jupiter's ring taken from the inside looking out.  Photobombed by the star...Betelgeuse.

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As NASA's Juno spacecraft flew through the narrow gap between Jupiter's radiation belts and the planet during its first science flyby, Perijove 1, on August 27, 2016, the Stellar Reference Unit (SRU-1) star camera collected the first image of Jupiter's ring taken from the inside looking out. The bright bands in the center of the image are the main ring of Jupiter's ring system.

 

While taking the ring image, the SRU was viewing the constellation Orion. The bright star above the main ring is Betelgeuse, and Orion's belt can be seen in the lower right. Juno's Radiation Monitoring Investigation actively retrieves and analyzes the noise signatures from penetrating radiation in the images of the spacecraft's star cameras and science instruments at Jupiter.

 

NASA's Jet Propulsion Laboratory manages the Juno mission for the principal investigator, Scott Bolton, of Southwest Research Institute in San Antonio. Juno is part of NASA's New Frontiers Program, which is managed at NASA's Marshall Space Flight Center in Huntsville, Alabama, for NASA's Science Mission Directorate. Lockheed Martin Space Systems, Denver, built the spacecraft. Caltech in Pasadena, California, manages JPL for NASA.

 

More information about Juno is online at http://www.nasa.gov/juno and http://missionjuno.swri.edu  

Higher resolution images at JPL Photojournal 

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LARGE AMOUNTS OF WATER ICE FOUND UNDERGROUND ON MARS

Article Link | Universe Today website

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By Irene Antonenko | Article Updated: 24 Dec , 2015


Many models predict that water ice shouldn’t be stable on Mars today, anywhere beyond the poles, no matter how deep you bury it. And yet, a recently published study shows that large regions outside the polar areas may, in fact, contain a relative abundance of water. This is exciting, not only because water has implications for the possibility of life on Mars, but also because it can provide a valuable resource to future explorers, both as a fuel and for life support. And if this water is near the equator, that makes it much easier to get to.


Over the past 7 years, lots of spacecraft observations have given us evidence for the presence of water on Mars, either at the surface or not far below. Radar data have shown that large amounts of water ice are stored at the poles (Lots of Pure Water Ice at Mars North Pole). And pictures of gullies have hinted at reserves of water beneath the surface (NASA Says Liquid Water Made Martian Gullies). Now, a team of scientists, led by Dr. William Feldman of the Planetary Science Institute in Tucson, Arizona, have taken a new look at some of that data.


Dr. Feldman and his team used data from the Mars Odyssey Neutron Spectrometer (MONS) to estimate the amount of water ice that is present outside of the polar regions of Mars, where water ice is not expected to be found. The MONS is an instrument that counts Martian neutrons from orbit. These “neutron counts” are sensitive to the presence of hydrogen and how deep it is below the surface. Using models that take the characteristics of the Martian surface and the relationship of hydrogen to water into account, the MONS data can be used to predict the amount and depth of water and water ice in the surface. Doing just that, Dr. Feldman’s team produced a nearly global map of potential underground ice deposits.


Fig1.thumb.jpg.895340e0fa09a891d57ba221e972649e.jpg

(The rest of the article can be read at Article Link above. Per Neowin rules regarding stories from other websites, this was the hard limit of what can be posted from the article.)

Yeah it's a bit dated (image is 2011), but WOW. AKA "HOLY ####!" ... to quote Avatar ... "Look at all that cheddar.". :yes: Nice to actually see this Global Map. Gonna plot it out on Mars Trek.

:yes: Saw that earlier today ... yeah buddy! And don't be surprised if a certain former ISS Commander with a lot of experience (*cough* one year stretch *cough*) decides that he'd be a great addition to SpaceX's Manned Spaceflight Program too ... 

 

Remember the thing from Elon ...

And Scott Kelly's response?

Pretty sure the Commander would like to go someplace more .. ehm ... distinguished. :D 

 

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NASA's Juno Spacecraft to Fly Over Jupiter's Great Red Spot July 10

 

Just days after celebrating its first anniversary in Jupiter orbit, NASA's Juno spacecraft will fly directly over Jupiter's Great Red Spot, the gas giant's iconic, 10,000-mile-wide (16,000-kilometer-wide) storm. This will be humanity's first up-close and personal view of the gigantic feature -- a storm monitored since 1830 and possibly existing for more than 350 years. 

 

"Jupiter's mysterious Great Red Spot is probably the best-known feature of Jupiter," said Scott Bolton, principal investigator of Juno from the Southwest Research Institute in San Antonio. "This monumental storm has raged on the solar system's biggest planet for centuries. Now, Juno and her cloud-penetrating science instruments will dive in to see how deep the roots of this storm go, and help us understand how this giant storm works and what makes it so special."

 

The data collection of the Great Red Spot is part of Juno's sixth science flyby over Jupiter's mysterious cloud tops. Perijove (the point at which an orbit comes closest to Jupiter's center) will be on Monday, July 10, at 6:55 p.m. PDT (9:55 p.m. EDT). At the time of perijove, Juno will be about 2,200 miles (3,500 kilometers) above the planet's cloud tops. Eleven minutes and 33 seconds later, Juno will have covered another 24,713 miles (39,771 kilometers) and will be directly above the coiling crimson cloud tops of Jupiter's Great Red Spot. The spacecraft will pass about 5,600 miles (9,000 kilometers) above the Giant Red Spot clouds. All eight of the spacecraft's instruments as well as its imager, JunoCam, will be on during the flyby.

 

On July 4 at 7:30 p.m. PDT (10:30 p.m. EDT), Juno will have logged exactly one year in Jupiter orbit. At the time, the spacecraft will have chalked up about 71 million miles (114.5 million kilometers) in orbit around the giant planet.

 

"The success of science collection at Jupiter is a testament to the dedication, creativity and technical abilities of the NASA-Juno team," said Rick Nybakken, project manager for Juno from NASA's Jet Propulsion Laboratory in Pasadena, California. "Each new orbit brings us closer to the heart of Jupiter's radiation belt, but so far the spacecraft has weathered the storm of electrons surrounding Jupiter better than we could have ever imagined."

 

Juno launched on Aug. 5, 2011, from Cape Canaveral, Florida. During its mission of exploration, Juno soars low over the planet's cloud tops -- as close as about 2,100 miles (3,400 kilometers). During these flybys, Juno is probing beneath the obscuring cloud cover of Jupiter and studying its auroras to learn more about the planet's origins, structure, atmosphere and magnetosphere.

 

Early science results from NASA's Juno mission portray the largest planet in our solar system as a turbulent world, with an intriguingly complex interior structure, energetic polar aurora, and huge polar cyclones.  

 

JPL manages the Juno mission for the principal investigator, Scott Bolton, of Southwest Research Institute. The Juno mission is part of the New Frontiers Program managed by NASA's Marshall Space Flight Center in Huntsville, Alabama, for the Science Mission Directorate. Lockheed Martin Space Systems, Denver, built the spacecraft. JPL is a division of Caltech in Pasadena. More information on the Juno mission is available at:

 

https://www.nasa.gov/juno 

http://missionjuno.org 

 

Bummer.  Guess there won't be any growing potatoes in the Martian surface.  

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Mars may be more toxic to life than we thought

 

Life on Mars … does it exist? Depending on when you last checked in with news about the Red Planet, you could probably be convinced either way. As we discover more and more about the composition and planetary dynamics of Mars, there has been cause for both elation and disappointment regarding the likelihood that organic life could manage to eke out a living on the planet.

 

The pendulum swung back toward the “no” side today with the release of a study examining how a special kind of salt on Mars interacts with ultraviolet radiation there. Martian soil is laced with perchlorates, an ion composed of one chlorine and four oxygen atoms, and which binds to a number of different elements to form various compounds. It’s classified as a salt, and was initially cause for celebration among extraterrestrial hopefuls because it drastically lowers the freezing point of water, meaning that liquid H20 might conceivably exist on the surface. It can also be used to produce rocket fuel and oxygen, another plus for future settlers.

 

It turns out that these perchlorates are actually highly toxic to life when bathed in UV radiation that pummels Mars. Researchers from the United Kingdom Centre for Astrobiology at the University of Edinburgh exposed a strain of bacteria commonly found on spacecraft to levels of perchlorates and UV light found on the Red Planet and found that nearly all of them were dead within a minute. They tried this with several different kinds of perchlorate, and found similar results every time. Adding in additional environmental factors found on Mars like low temperatures, additional minerals found on Mars and a lack of oxygen also failed to keep the bacteria alive.

 

/snip

 

Full article at Astronomy Magazine

Each Shuttle booster contained 315,000 kg, so 630,000 kg for the pair, of ammonium perchlorate, some of which fell unburned on the Cape.  It's also used in fertilizer and explosives.

 

Perchlorates are also common in water supplies, so removal methods are known,

 

https://www.wqpmag.com/perchlorate-removal

True, and those examples are useful ways of using them in controlled ways; plus when the more harmful varieties fall to Earth their environmental impact is minimal. The Florida climate sees lots of rain and humidity to dissipate them rapidly.

 

The kinds on Mars are more varied than we typically see on Earth, with an abundance of magnesium perchlorate, magnesium chlorate and sodium perchlorate (citation: https://en.wikipedia.org/wiki/Perchlorate#On_Mars, paragraph 5 | S2) in the form of hydrated salts. I'm sure Salt Mines encounter these perchlorates all the time; in fact the sodium-based one (sodium perchlorate) is salt, produced by anodic oxidation of sodium chlorate at an inert electrode, such as platinum (citation: https://en.wikipedia.org/wiki/Sodium_perchlorate#Production). It also has medical uses.

 

The only real issue with the perchlorates is their abundance in the Martian soil. "Further findings of perchlorate and chlorate in the Martian meteorite EETA79001 [20] and by the Mars Curiosity rover in 2012-2013 support the notion that perchlorates are globally distributed throughout the Martian surface.[21][22][23] With concentrations approaching .5% and exceeding toxic levels on Martian soil, Martian perchlorates would present a serious challenge to human settlement." (Citation: https://en.wikipedia.org/wiki/Perchlorate#On_Mars paragraph 4).

 

Can we do something about these perchlorates? Sure. We can do lots of things with them, too. But we need to be careful about exposure. That's all I'm saying.

 

Make solid rocket propellants, extract the Mg, Cl etc. by putting them through extraction  processes....

 

Turn the problem around and look at them as a chemical  resource.

 

https://www.researchgate.net/publication/242525435_Perchlorate_on_Mars_A_chemical_hazard_and_a_resource_for_humans

  • 4 weeks later...

The Colorado School of Mines, the NCAA "Orediggers," is ranked as one of the top schools in the world for mine engineering.

 

 


http://space.mines.edu

 

Quote

>
Mines is planning to launch in 2018 a multi-disciplinary graduate program in Space Resources to offer a Post-Baccalaureate certificate and a Master of Science degree for college graduates and professionals interested in this emerging arena. Qualified students who want to pursue research through a Ph.D. in collaborating departments at Mines are also sought. The proposed program will focus on developing core knowledge and gaining design practices in systems for responsible exploration, extraction, and use of resources in the Solar System.
>

Edited by DocM
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Cassini to Begin Final Five Orbits Around Saturn

 

NASA's Cassini spacecraft will enter new territory in its final mission phase, the Grand Finale, as it prepares to embark on a set of ultra-close passes through Saturn’s upper atmosphere with its final five orbits around the planet.

 

Cassini will make the first of these five passes over Saturn at 12:22 a.m. EDT Monday, Aug. 14. The spacecraft's point of closest approach to Saturn during these passes will be between about 1,010 and 1,060 miles (1,630 and 1,710 kilometers) above Saturn's cloud tops.

 

The spacecraft is expected to encounter atmosphere dense enough to require the use of its small rocket thrusters to maintain stability – conditions similar to those encountered during many of Cassini's close flybys of Saturn's moon Titan, which has its own dense atmosphere.

 

"Cassini's Titan flybys prepared us for these rapid passes through Saturn's upper atmosphere," said Earl Maize, Cassini project manager at NASA's Jet Propulsion Laboratory (JPL) in California. "Thanks to our past experience, the team is confident that we understand how the spacecraft will behave at the atmospheric densities our models predict."

 

Maize said the team will consider the Aug. 14 pass nominal if the thrusters operate between 10 and 60 percent of their capability. If the thrusters are forced to work harder – meaning the atmosphere is denser than models predict – engineers will increase the altitude of subsequent orbits. Referred to as a "pop-up maneuver,” thrusters will be used to raise the altitude of closest approach on the next passes, likely by about 120 miles (200 kilometers).

 

If the pop-up maneuver is not needed, and the atmosphere is less dense than expected during the first three passes, engineers may alternately use the "pop-down" option to lower the closest approach altitude of the last two orbits, also likely by about 120 miles (200 kilometers). Doing so would enable Cassini's science instruments, especially the ion and neutral mass spectrometer (INMS), to obtain data on the atmosphere even closer to the planet's cloud tops.

 

"As it makes these five dips into Saturn, followed by its final plunge, Cassini will become the first Saturn atmospheric probe," said Linda Spilker, Cassini project scientist at JPL. "It's long been a goal in planetary exploration to send a dedicated probe into the atmosphere of Saturn, and we're laying the groundwork for future exploration with this first foray."

 

Other Cassini instruments will make detailed, high-resolution observations of Saturn's auroras, temperature, and the vortexes at the planet's poles. Its radar will peer deep into the atmosphere to reveal small-scale features as fine as 16 miles (25 kilometers) wide – nearly 100 times smaller than the spacecraft could observe prior to the Grand Finale.

 

On Sept. 11, a distant encounter with Titan will serve as a gravitational version of a large pop-down maneuver, slowing Cassini’s orbit around Saturn and bending its path slightly to send the spacecraft toward its Sept. 15 plunge into the planet.

 

During the half-orbit plunge, the plan is to have seven Cassini science instruments, including INMS, turned on and reporting measurements in near real time. The spacecraft is expected to reach an altitude where atmospheric density is about twice what it encountered during its final five passes. Once Cassini reaches that point, its thrusters will no longer be able to work against the push of Saturn’s atmosphere to keep the spacecraft's antenna pointed toward Earth, and contact will permanently be lost. The spacecraft will break up like a meteor moments later, ending its long and rewarding journey.

 

NASA

 

Orbit 288 - August 10 - August 17

 

  • Cassini has just five orbits of Saturn remaining before the mission ends.
  • During this orbit, Cassini’s Composite Infrared Spectrometer (CIRS)observes the edge of Saturn’s atmosphere to determine different temperatures at different altitudes.
  • The spacecraft’s imaging cameras, the Imaging Science Subsystem (ISS), then observe mysterious features informally called “streaks” in Saturn’s C ring.
  • This is the first of five orbits in which Cassini’s elliptical orbit carries it so low that the spacecraft passes briefly through Saturn’s outermost atmosphere. Cassini’s reaction control thrusters are at the ready to correct the spacecraft’s orientation in case Saturn’s atmosphere pushes on the spacecraft hard enough to cause any rotation.
  • During the period in which the spacecraft is nearest Saturn, Cassini’s Ion and Neutral Mass Spectrometer (INMS) performs the first ever direct sampling of Saturn’s  atmosphere. The instrument measures densities of different species of molecular hydrogen, helium and a variety of ions in the immediate vicinity of the spacecraft.
  • Cassini’s RADAR instrument operates at the same time as INMS, studying Saturn’s atmosphere in a passive mode to study the small-scale structure and ammonia concentration of Saturn’s atmosphere.
  • During this orbit, Cassini gets within 1,060 miles (1,710 kilometers) of Saturn’s 1-bar level. Cassini also passes within 3,720 miles (5,990 kilometers) of the inner edge of Saturn’s D ring.

 

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