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Astronomers release spectacular survey of the distant universe

 

 

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An image of a small section (0.4%) of the UDS field. Most of the objects in the image are very distant galaxies, observed as they were over 9 billion years ago. In the full image, 250,000 galaxies have been detected over an area of sky four times the size of the full Moon. Credit: Omar Almaini, University of Nottingham.

 

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Astronomers at The University of Nottingham have released spectacular new infrared images of the distant Universe, providing the deepest view ever obtained over a large area of sky. The team, led by Omar Almaini, Professor of Astrophysics in the School of Physics and Astronomy, is presenting their results at the National Astronomy Meeting taking place this week at the University's Jubilee Campus.

 

The final data release from the Ultra-Deep Survey (UDS) maps an area four times the size of the full Moon to unprecedented depth. Over 250,000 galaxies have been detected, including several hundred observed within the first billion years after the Big Bang. Astronomers around the world will use the new images to study the early stages of galaxy formation and evolution.

 

The release of the final UDS images represents the culmination of a project that began taking data in 2005. The scientists used the United Kingdom Infrared Telescope (UKIRT) on Hawaii to observe the same patch of sky repeatedly, building up more than 1,000 hours of exposure time. Observing in the infrared is vital for studying the distant Universe, as ordinary starlight is "redshifted" to longer wavelengths due to the cosmological expansion of the Universe.

 

Because of the finite speed of light, the most distant galaxies are also observed very far back in time.

 

Professor Almaini, said: "With the UDS we can study distant galaxies in large numbers, and observe how they evolved at different stages in the history of the Universe. We see most of the galaxies in our image as they were billions of years before the Earth was formed."

 

The UDS is the deepest of five projects, collectively known as the UKIRT Infrared Deep Sky Survey (UKIDSS).

 

Earlier releases of data from the UDS have already produced a wide range of scientific advances, including studies of the earliest galaxies in the first billion years after the Big Bang, measurements of the build-up of galaxies through cosmic time, and studies of the large-scale distribution of galaxies to weigh the mysterious 'dark matter' that pervades the cosmos. The added depth from the new release is expected to produce many new breakthroughs.

http://www.eurekalert.org/pub_releases/2016-06/uon-ars063016.php

 

 

Zoomable optical/IR image, using data from the B, z and K filters.     (slider controls on the panel, 2 filter groups)

 

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approximately 4x4 arcmin on the side, representing ~0.5% of the UDS image.  Credit: Omar Almaini, University of Nottingham.

 

 

The full image may be downloaded here (37Mb).

 

source.....

Astronomers release spectacular survey of the distant Universe

http://www.nottingham.ac.uk/news/pressreleases/2016/june/astronomers-release-spectacular-survey-of-the-distant-universe.aspx

 

:)

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Xinhua Insight: Installation complete on world's largest radio telescope

 

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PINGTANG, July 3, 2016 (Xinhua) -- The aerial photo taken on July 3, 2016 shows the Five-hundred-meter Aperture Spherical Telescope (FAST) in Pingtang County, southwest China's Guizhou Province. Installation was completed on the world's largest radio telescope on Sunday morning as the last of 4,450 panels was fitted into the center of the big dish. Scientists will then begin debugging and trial observation of the FAST. (Xinhua/Liu Xu)

 

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GUIYANG, July 3 (Xinhua) -- Installation was completed on the world's largest radio telescope on Sunday morning as the last of 4,450 panels was fitted into the center of the big dish.

 

Hoisting of the last triangular panel to the reflector, which is the size of 30 football fields, began at 10:47 a.m. and lasted about an hour. It was a landmark step for the telescope's planned launch of operations in September.

 

About 300 people, including builders, experts, science fiction enthusiasts and reporters, witnessed the installation at a karst valley in Pingtang County in the southwestern province of Guizhou.

 

"The telescope is of great significance for humans to explore the universe and extraterrestrial civilizations," said Liu Cixin, a renowned science fiction writer, at the site.

 

"I hope scientists can make epoch-making discoveries," said Liu, who won the 2015 Hugo Award for Best Novel.

 

Scientists will then begin debugging and trial observation of the Five-hundred-meter Aperture Spherical Telescope (FAST), said Zheng Xiaonian, deputy head of the National Astronomical Observation (NAO) under the Chinese Academy of Sciences, which built the telescope.

 

The project has the potential to search for more strange objects to better understand the origin of the universe and boost the global hunt for extraterrestrial life, said Zheng.

 

Zheng said the radio telescope will be the global leader for the next 10 to 20 years.

 

In the first two or three years after its completion, the telescope will undergo further adjustment, and during that period Chinese scientists will use it for early-stage research. After that, it will be open to scientists worldwide, said Peng Bo, director of the NAO Radio Astronomy Technology Laboratory.

 

Scientists can also carry out remote control and observation in other cities such as Beijing, more than 2,000 kilometers from the telescope site, said Peng.

 

Upon completion, the telescope will dwarf Puerto Rico's Arecibo Observatory, which is 300 meters in diameter. It will also be 10 times more sensitive than the steerable 100-meter telescope near Bonn, Germany, he said.

 

"Most of the technology and materials are domestically made," said Wang Qiming, chief technologist of the FAST project.

 

Among the 7 FAST receivers, five were domestically made and another two were co-produced by Chinese, Australian and American institutions.

 

Work on the 1.2-billion-yuan (180 million U.S. dollars) FAST project began in 2011.

more at the link...

http://news.xinhuanet.com/english/2016-07/03/c_135485389.htm

 

 

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PINGTANG, July 3, 2016 (Xinhua) -- The last triangular panel to the reflector of the Five-hundred-meter Aperture Spherical Telescope (FAST) is being installed in Pingtang County, southwest China's Guizhou Province, July 3, 2016. Installation was completed on the world's largest radio telescope on Sunday morning as the last of 4,450 panels was fitted into the center of the big dish. Scientists will then begin debugging and trial observation of the FAST. (Xinhua/Ou Dongqu)

 

 

135485389_14675363568761n.jpg

PINGTANG, July 3, 2016 (Xinhua) -- The last triangular panel to the reflector of the Five-hundred-meter Aperture Spherical Telescope (FAST) is being installed in Pingtang County, southwest China's Guizhou Province, July 3, 2016. Installation was completed on the world's largest radio telescope on Sunday morning as the last of 4,450 panels was fitted into the center of the big dish. Scientists will then begin debugging and trial observation of the FAST. (Xinhua/Liu Xu)

 

135485389_14675363569461n.jpg

PINGTANG, July 3, 2016 (Xinhua) -- Balloons are released to celebrate the complete installation of the Five-hundred-meter Aperture Spherical Telescope (FAST) in Pingtang County, southwest China's Guizhou Province, July 3, 2016. Installation was completed on the world's largest radio telescope on Sunday morning as the last of 4,450 panels was fitted into the center of the big dish. Scientists will then begin debugging and trial observation of the FAST. (Xinhua/Liu Xu)

 

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PINGTANG, July 3, 2016 (Xinhua) 

 

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PINGTANG, July 3, 2016 (Xinhua) 

 

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PINGTANG, July 3, 2016 (Xinhua)

 

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PINGTANG, July 3, 2016 (Xinhua) -- A worker installs the last triangular panel to the reflector of the Five-hundred-meter Aperture Spherical Telescope (FAST) in Pingtang County, southwest China's Guizhou Province, July 3, 2016. Installation was completed on the world's largest radio telescope on Sunday morning as the last of 4,450 panels was fitted into the center of the big dish. Scientists will then begin debugging and trial observation of the FAST. (Xinhua/Ou Dongqu)

 

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PINGTANG, July 3, 2016 (Xinhua) -- Combined photo shows picture of the first panel to the reflector being installed on the Five-hundred-meter Aperture Spherical Telescope (FAST) at a karst valley in Pingtang County of southwest China's Guizhou Province on Aug. 2, 2015 (up) and picture of nearly-done project of the FAST taken on July 2, 2016. Installation was completed on the world's largest radio telescope on Sunday morning as the last of 4,450 panels was fitted into the center of the big dish. Scientists will then begin debugging and trial observation of the FAST. The project has the potential to search for more strange objects to better understand the origin of the universe and boost the global hunt for extraterrestrial life. (Xinhua/Ou Dongqu)

 

many more images at the link...

http://news.xinhuanet.com/english/2016-07/03/c_135485389.htm

 

:D

Hubble Captures the Beating Heart of the Crab Nebula

 

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This image is a composite of separate exposures acquired by the ACS/WFC instrument. Several filters were used to sample various wavelengths. The color results from assigning different hues (colors) to each monochromatic (grayscale) image associated with an individual filter. In this case, the assigned colors represent not only changes in different filters, but also the same filters taken on different exposure dates to highlight features that change over time.

 

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Credit: NASA and ESA
Acknowledgment: J. Hester (ASU) and M. Weisskopf (NASA/GSFC)

 

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JULY 7, 2016: At the center of the Crab Nebula, located in the constellation Taurus, lies a celestial "beating heart" that is an example of extreme physics in space. The tiny object blasts out blistering pulses of radiation 30 times a second with unbelievable clock-like precision.

 

Astronomers soon figured out that it was the crushed core of an exploded star, called a neutron star, which wildly spins like a blender on puree. The burned-out stellar core can do this without flying apart because it is 10 billion times stronger than steel. This incredible density means that the mass of 1.4 suns has been crushed into a solid ball of neutrons no bigger than the width of a large city.

 

This Hubble image captures the region around the neutron star. It is unleashing copious amounts of energy that are pushing on the expanding cloud of debris from the supernova explosion — like an animal rattling its cage. This includes wave-like tsunamis of charged particles embedded in deadly magnetic fields.

 

On July 4, 1054, Chinese astronomers recorded the supernova that formed the Crab Nebula. The ultimate celestial firework, this "guest star" was visible during the daytime for 23 days, shining six times brighter than the planet Venus.

 

The supernova was also recorded by Japanese, Arabic, and Native American stargazers. While searching for a comet that was predicted to return in 1758, French astronomer Charles Messier discovered a hazy nebula in the direction of the long-vanished supernova. He would later add it to his celestial catalog as "Messier 1." Because M1 didn't move across the sky like a comet, Messier simply ignored it other than just marking it as a "fake comet."

 

Nearly a century later the British astronomer William Parsons sketched the nebula. Its resemblance to a crustacean led to M1's other name, the Crab Nebula. In 1928 Edwin Hubble first proposed associating the Crab Nebula to the Chinese "guest star" of 1054.

http://hubblesite.org/newscenter/archive/releases/2016/26/

 

Quote

This image is a composite of separate exposures acquired by the ACS/WFC instrument. Several filters were used to sample various wavelengths. The color results from assigning different hues (colors) to each monochromatic (grayscale) image associated with an individual filter. In this case, the assigned colors represent not only changes in different filters, but also the same filters taken on different exposure dates to highlight features that change over time.

 

hs-2016-26-b-web_print.jpg

Credit: NASA and ESA
Acknowledgment: J. Hester (ASU) and M. Weisskopf (NASA/GSFC)

  • Like 3

Surprising neutrino decoherence inside supernovae

 

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Neutrinos are elementary particles known for displaying weak interactions. As a result, neutrinos passing each other in the same place hardly notice one another. Yet, neutrinos inside a supernova collectively behave differently because of their extremely high density. A new study reveals that neutrinos produced in the core of a supernova are highly localised compared to neutrinos from all other known sources. This result stems from a fresh estimate for an entity characterising these neutrinos, known as wave packets, which provide information on both their position and their momentum. These findings have just been published in EPJ C by Jörn Kersten from the University of Bergen, Norway, and his colleague Alexei Yu. Smirnov from the Max Planck Institute for Nuclear Physics in Heidelberg, Germany. The study suggests that the wave packet size is irrelevant in simpler cases. This means that the standard theory for explaining neutrino behaviour, which does not rely on wavepackets, now enjoys a more sound theoretical foundation.

 

One of the laws governing particles at the quantum scale - called the uncertainty principle - tells us that we cannot simultaneously know a particle's position and momentum (which is the product of their mass times their velocity) with arbitrary precision. Particles like neutrinos are therefore described by a mathematical entity, called wave packets, the size of which determines the uncertainty in the neutrino's position and momentum.

 

The authors find that neutrino wave packets in supernovae are unusually small in size. This implies that each individual neutrino displays decoherence. Kersten and Smirnov, however, show that this decoherence effect does not have any impact on the experimental measurement of the oscillation probability for each neutrino flavour; they only demonstrate this result in cases that are similar to, albeit simpler, than what happens in a supernova, where collective effects occur.

 

In this study, the authors thus provide a theoretical motivation to the use of the standard description of supernova neutrinos, which does not rely on wave packets. Indeed, their findings suggest that collective effects are also unaffected by the neutrino wave packet size, a premise that has yet to be proven.

http://www.eurekalert.org/pub_releases/2016-07/s-snd071216.php

 

Abstract

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Astronomers map a record-breaking 1.2 million galaxies to study the secrets of dark energy

 

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Astronomers announced this week the sharpest results yet on the properties of dark energy -- hundreds of scientists from the Sloan Digital Sky Survey III collaborated to make the largest-ever, 3-D map of distant galaxies

 

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This is one slice through the map of the large-scale structure of the Universe from the Sloan Digital Sky Survey and its Baryon Oscillation Spectroscopic Survey. Each dot in this picture indi-cates the position of a galaxy 6 billion years into the past. The image covers about 1/20th of the sky, a slice of the Universe 6 billion light-years wide, 4.5 billion light-years high, and 500 million light-years thick. Color indicates distance from Earth, ranging from yellow on the near side of the slice to purple on the far side. Galaxies are highly clustered, revealing superclusters and voids whose presence is seeded in the first fraction of a second after the Big Bang. This image contains 48,741 galaxies, about 3% of the full survey dataset. Grey patches are small regions without survey data.
CREDIT
Daniel Eisenstein and SDSS-III

 

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Astronomers announced this week the sharpest results yet on the properties of dark energy. Hundreds of scientists, among them Marcos Pellejero Ibañez and Jose Alberto Rubiño from the Instituto de Astrofísica de Canarias (IAC), and other Spanish institutions as the Instituto de Ciencias del Cosmos from the University of Barcelona (ICCUB) and the Instituto de Física Teórica (UAM-CSIC) from the Sloan Digital Sky Survey III (SDSS-III), collaborated to make the largest-ever, three-dimensional map of distant galaxies. The scientists then used this map to make one of the most precise measurements yet of the dark energy currently driving the accelerated expansion of the Universe.

 

"We have spent a decade collecting measurements of 1.2 million galaxies over one quarter of the sky to map out the structure of the Universe over a volume of 650 cubic billion light years," says Dr. Jeremy Tinker of New York University, a co-leader of the scientific team that led this effort. "This map has allowed us to make the best measurements yet of the effects of dark energy in the expansion of the Universe. We are making our results and map available to the world."

 

These new measurements were carried out by the Baryon Oscillation Spectroscopic Survey (BOSS) program of SDSS-III. Shaped by a continuous tug-of-war between dark matter and dark energy, the map revealed by BOSS allows astronomers to measure the expansion rate of the Universe and thus determine the amount of matter and dark energy that make up the present-day Universe. A collection of papers describing these results was submitted this week to the Monthly Notices of the Royal Astronomical Society.

 

BOSS measures the expansion rate of the Universe by determining the size of the baryonic acoustic oscillations (BAO) in the three-dimensional distribution of galaxies. The original BAO size is determined by pressure waves that travelled through the young Universe up to when it was only 400,000 years old (the Universe is presently 13.8 billion years old), at which point they became frozen in the matter distribution of the Universe. The end result is that galaxies are preferentially separated by a characteristic distance, that astronomers call the acoustic scale. The size of the acoustic scale at 13.4 billion years ago has been exquisitely determined from observations of the cosmic microwave background from the light emitted when the pressure waves became frozen. Measuring the distribution of galaxies since that time allows astronomers to measure how dark matter and dark energy have competed to govern the rate of expansion of the Universe.

 

To measure the size of these ancient giant waves to such sharp precision, BOSS had to make an unprecedented and ambitious galaxy map, many times larger than previous surveys. At the time the BOSS program was planned, dark energy had been previously determined to significantly influence the expansion of the Universe starting about 5 billion years ago. BOSS was thus designed to measure the BAO feature from before this point (7 billion years ago) out to near the present day (2 billion years ago).

 

The map also reveals the distinctive signature of the coherent movement of galaxies toward regions of the Universe with more matter, due to the attractive force of gravity. Crucially, the observed amount of infall is explained well by the predictions of general relativity. This agreement supports the idea that the acceleration of the expansion rate is driven by a phenomenon at the largest cosmic scales, such as dark energy, rather than a breakdown of our gravitational theory.

more at the link...

http://www.eurekalert.org/pub_releases/2016-07/idad-ama071416.php

 

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The Sloan Digital Sky Survey and its Baryon Oscillation Spectroscopic Survey has transformed a two-dimensional image of the sky (left panel) into a three-dimensional map spanning distances of billions of light years, shown here from two perspectives (middle and right panels). This map includes 120,000 galaxies over 10% of the survey area. The brighter regions correspond to the regions of the Universe with more galaxies and therefore more dark matter.
CREDIT
Jeremy Tinker and SDSS-III

 

There are 2 stories running with the same data, published, but for different aspects of the collaborative venture...

 

Astronomers map a record-breaking 1.2 million galaxies to study the secrets of dark energy

http://www.eurekalert.org/pub_releases/2016-07/idad-ama071416.php

 

The clustering of galaxies in the completed SDSS-III Baryon Oscillation Spectroscopic Survey: double-probe measurements from BOSS galaxy clustering \& Planck data -- towards an analysis without informative priors

paper

 

and

 

Dark energy measured with record-breaking map of 1.2 million galaxies

http://www.eurekalert.org/pub_releases/2016-07/dbnl-dem071416.php

 

The clustering of galaxies in the completed SDSS-III Baryon Oscillation Spectroscopic Survey: cosmological analysis of the DR12 galaxy sample

paper

 

The scope of this is huge...and after the next mapping.... "dark matter" behavior?

  • Like 2

This one is way to neat.....

 

A 'matryoshka' in the interstellar medium

 

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The discovery of this triple-bubble, made up of 3 supernova shells and observed by scientist of the Instituto de Astrofísica de Canarias (IAC), allows to understand the feedback processes in galaxy discs

 

INSTITUTO DE ASTROFÍSICA DE CANARIAS (IAC)

 

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This is an artistic representation of the object showing the stellar cluster surrounded by the three bubbles.
CREDIT
Gabriel Pérez/SMM (IAC).

 

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As if it were one of the known Russian dolls, a group of astronomers, led by researchers at the Instituto de Astrofísica de Canarias, (IAC) has found the first known case of three supernova remnants one inside the other. Using the programme BUBBLY, a method developed within the group for detecting huge expanding bubbles of gas in interstellar space, they were observing the galaxy M33 in our Local Group of galaxies and found example of a triple-bubble. The results, which were published yesterday in the journal Monthly Notices of the Royal Astronomical Society, help to understand the feedback phenomenon, a fundamental process of star formation and in the dissemination of metals produced in massive stars.

 

The group has been building up a data base of these superbubbles with observations of a number of galaxies and, using the very high resolution 2D spectrograph, GHaFaS (Galaxy Halpha Fabry-Perot System), on the 4.2 m William Herschel Telescope (WHT) of the Isaac Newton Group of Telescopes (Roque de los Muchachos Observatory, La Palma), has been able to detect and measure these superbubbles, which range in size from a few light years to as big as a thousand light years across.

 

Superbubbles around large young star clusters are known to have a complex structure due to the effects of powerful stellar winds and supernova explosions of individual stars, whose separate bubbles may end up merging into a superbubble, but this is the first time that they, or any other observers, have found three concentric expanding supernova shells.

 

"This phenomenon -says John Beckman, one of the co-authors on the paper- allows to explore the interstellar medium in a unique way, we can measure how much matter there is in a shell, approximately a couple of hundred times the mass of the sun in each of the shells". However, if it is known that a supernova expels only around ten times the mass of the sun, where do the second and third shells get their gas from if the first supernova sweeps up all the gas?

 

The answer to that must come from the surrounding gas and in the inhomogeneous interstellar medium. "It must be -says Artemi Camps Fariña, who is first author on the paper-, that the interstellar medium is not at all uniform, there must be dense clumps of gas, surrounded by space with gas at a much lower density. A supernova does not just sweep up gas, it evaporates the outsides of the clumps, leaving some dense gas behind which can make the second and the third shells".

 

"The presence of the bubbles -adds Artemi- explains why star formation has been much slower than simple models of galaxy evolution predicted. These bubbles are part of a widespread feedback process in galaxy disc and if it were not for feedback, spiral galaxies would have very short lives, and our own existence would be improbable", concludes. The idea of an inhomogeneous interstellar medium is not new, but the triple bubble gives a much clearer and quantitative view of the structure and the feedback process. The results will help theorists working on feedback to a better understanding of how this process works in all galaxy discs.

http://www.eurekalert.org/pub_releases/2016-07/idad-ai071416.php

 

:woot:

  • Like 3

Some of the stuff that the SLOAN survey and BOSS have put out are amazing to see. I'm going to gather a guess though that down the road, BOSS will (or its next variant) actually discover something we either missed or didn't think of when it comes to dark energy etc.

 

Also that 3D slice of the universe they put out from SLOAN and BOSS, I can't help but think it looks like a cross section of a sponge. I know that's been said many times over the decades now since we've seen these images done and all - but now more than ever it really does come across as a sponge of some sort to me. As someone who studied astrophysics in college, my old brain just can't anymore :D

  • Like 2

@LOC    You are being modest as you have a wealth of knowledge.

 

As a side note, I have issues with the use of "dark anything" as I deem it a "placeholder" for an unknown. In time, this "placeholder" will be defined.

 

IMHO, the appearance of the structure of the universe is akin to a "sponge" due to clumping caused by the "placeholder" and is a very good descriptor in my view.

 

// That triple gas ring was pretty neat......:D

 

  • Like 2

Thanks :blush: 

 

And yes, Dark Energy and Dark Matter (and even Dark Gravity if you go down that rabbit hole) are only really just placeholders for whatever it is we either haven't figured out or discovered in so called motion. I'm sure within 20 years we'll have at least named one of those more in line with what it actually is (either an undiscovered massive elementary particle or something else).

 

And yes, the triple gas ring is pretty neat. When things line up with our line of sight in the universe, it can look astoundingly beautiful to see.

  • Like 2
  • 3 weeks later...

Chorus of black holes radiates X-rays

 

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The blue dots in this field of galaxies, known as the COSMOS field, show galaxies that contain supermassive black holes emitting high-energy X-rays. They were detected by NASA's Nuclear Spectroscopic Array, or NuSTAR, which spotted 32 such black holes in this field and has observed hundreds across the whole sky so far.

The other colored dots are galaxies that host black holes emitting lower-energy X-rays, and were spotted by NASA's Chandra X-ray Observatory. Chandra data show X-rays with energies between 0.5 to 7 kiloelectron volts, while NuSTAR data show X-rays between 8 to 24 kiloelectron volts.
CREDIT
NASA/JPL-Caltech

 

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Supermassive black holes do not give off any of their own light, hence the word "black" in their name. However, many black holes pull in, or accrete, surrounding material, and emit powerful bursts of X-rays. Collectively, these active black holes throughout the sky can be thought of a cosmic choir, singing in the language of X-rays. Their "song" is what astronomers call the cosmic X-ray background.

 

To date, NASA's Chandra mission has managed to pinpoint many of the individual black holes contributing to the X-ray background, but the ones that let out high-energy X-rays--those with the highest-pitched "voices"--have remained elusive.

 

New data from NASA's Nuclear Spectroscopic Telescope Array, or NuSTAR, has, for the first time, begun to pinpoint large numbers of the black holes sending out the high-energy X-rays. More technically, NuSTAR has made significant progress in resolving the high-energy X-ray background.

 

"We've gone from resolving just 2 percent of the high-energy X-ray background to 35 percent," says Fiona Harrison, Benjamin M. Rosen Professor of Physics and Astronomy at Caltech, the principal investigator of NuSTAR, and lead author of a new study describing the findings in an upcoming issue of The Astrophysical Journal. "We can see the most obscured black holes, hidden in thick gas and dust."

 

The results will ultimately help astronomers understand how the growth patterns of supermassive black holes change over time--a key factor in the development of black holes and the galaxies that host them. For instance, the supermassive black hole at the center of our Milky Way galaxy is dormant now, but at some point in the past, it would have siphoned gas and bulked up in size.

 

As black holes grow, their intense gravity pulls matter toward them. The matter heats up to extremely high temperatures and particles get boosted to close to the speed of light. Together, these processes make the black hole surroundings glow with X-rays. A supermassive black hole with an ample supply of fuel, or gas, will give off more high-energy X-rays.

 

NuSTAR is the first telescope capable of focusing these high-energy X-rays into sharp pictures.

 

"Before NuSTAR, the X-ray background in high-energies was just one blur with no resolved sources," says Harrison. "To untangle what's going on, you have to pinpoint and count up the individual sources of the X-rays."

 

"We knew this cosmic choir had a strong high-pitched component, but we still don't know if it comes from a lot of smaller, quiet singers, or a few with loud voices," says coauthor Daniel Stern, the project scientist for NuSTAR at JPL. "Now, thanks to NuSTAR, we're gaining a better understanding of the black holes and starting to address these questions."

 

High-energy X-rays can reveal what lies around the most obscured supermassive black holes, which are otherwise hard to see. In the same way that medical X-rays can travel through your skin to reveal pictures of bones, NuSTAR can see through the gas and dust around black holes, to get a deeper view of what is going on inside.

 

With NuSTAR's more complete picture of supermassive black hole populations, astronomers can begin to puzzle together how these objects evolve and change over time. When did they start and stop growing? What is the distribution of the gas and dust that both feed and hide the black holes?

 

The team expects that over time, NuSTAR will be able to resolve more of the high-energy X-ray background--and better decipher the X-ray song of the universe's black holes.

http://www.eurekalert.org/pub_releases/2016-07/ciot-cob072816.php

 

//

As a side note, I found this interesting...

Neutrinos Hint of Matter-Antimatter Rift

https://www.quantamagazine.org/20160728-neutrinos-hint-matter-antimatter-asymmetry/

 

:)

  • Like 3

UCLA astronomers make first accurate measurement of oxygen in distant galaxy

 

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Galaxy COSMOS-1908 is in the center of this Hubble Space Telescope image, indicated by the arrow. Nearly everything in the image is a galaxy; many of these galaxies are much closer to the Earth than COSMOS-1908.
CREDIT
Ryan Sanders and the CANDELS team

 

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UCLA astronomers have made the first accurate measurement of the abundance of oxygen in a distant galaxy. Oxygen, the third-most abundant chemical element in the universe, is created inside stars and released into interstellar gas when stars die. Quantifying the amount of oxygen is key to understanding how matter cycles in and out of galaxies.

 

This research is published online in the Astrophysical Journal Letters, and is based on data collected at the W. M. Keck Observatory on Mauna Kea, in Hawaii.

 

"This is by far the most distant galaxy for which the oxygen abundance has actually been measured," said Alice Shapley, a UCLA professor of astronomy, and co-author of the study. "We're looking back in time at this galaxy as it appeared 12 billion years ago."

 

Knowing the abundance of oxygen in the galaxy called COSMOS-1908 is an important stepping stone toward allowing astronomers to better understand the population of faint, distant galaxies observed when the universe was only a few billion years old and galaxy evolution, Shapley said.

 

COSMOS-1908, contains approximately 1 billion stars. In contrast, the Milky Way contains approximately 100 billion stars; some galaxies in the universe contain many more, while others contain many fewer. Furthermore, COSMOS-1908 contains approximately only 20 percent the abundance of oxygen that is observed in the sun.

 

Typically, astronomers rely on extremely indirect and imprecise techniques for estimating oxygen abundance for the vast majority of distant galaxies. But in this case, UCLA researchers used a direct measurement, said Ryan Sanders, astronomy graduate student and the study's lead author.

 

"Close galaxies are much brighter, and we have a very good method of determining the amount of oxygen in nearby galaxies," Sanders said. In faint, distant galaxies, the task is dramatically more difficult, but COSMOS-1908 was one case for which Sanders was able to apply the "robust" method commonly applied to nearby galaxies. "We hope this will be the first of many," he said.

 

Shapley said that prior to Sanders' discovery researchers didn't know if they could measure how much oxygen there was in these distant galaxies.

"Ryan's discovery shows we can measure the oxygen and compare these observations with models of how galaxies form and what their history of star formation is," Shapley said.

 

The amount of oxygen in a galaxy is determined primarily by three factors: how much oxygen comes from large stars that end their lives violently in supernova explosions -- a ubiquitous phenomenon in the early universe, when the rate of stellar births was dramatically higher than the rate in the universe today; how much of that oxygen gets ejected from the galaxy by so-called "super winds," which propel oxygen and other interstellar gases out of galaxies at hundreds of thousands of miles per hour; and how much pristine gas enters the galaxy from the intergalactic medium, which doesn't contain much oxygen.

 

"If we can measure how much oxygen is in a galaxy, it will tell us about all these processes," said Shapley, who, along with Sanders, is interested in learning how galaxies form and evolve, why galaxies have different structures, and how galaxies exchange material with their intergalactic environments.

more at the link...

http://www.eurekalert.org/pub_releases/2016-08/uoc--uam080316.php

 

Measuring Oxygen In A Distant Galaxy

http://spaceref.com/astronomy/measuring-oxygen-in-a-distant-galaxy.html

 

:)

  • Like 3

This is just a post of "beauty"...

 

Floating in Space: Milky Way Reflections on Mirror-Like Salt Flats

 

Quote

Perhaps nowhere on Earth is there a more beautiful place to take in crystal-clear views of the starlit sky than the pristine Salar de Uyuni in southwest Bolivia, which boasts a mirror-like reflective surface in some spots. The largest salt flat in the world provides an incredible setting for photographer Daniel Kordan, who traveled there in search of the darkest possible sky. Avoiding light pollution can be tough even in rural areas, but not only is this mineral-coated landscape sufficiently far from urban areas, it’s also sort of alien-like in its own right.

 

In an interview with My Modern Met, Kordan says the salt flats were so dark, he couldn’t see anything at all until his eyes adjusted. Then, suddenly, the stars were underneath him as well as above. “It seemed that we floated in open space. Our spaceship is parked in a distance, and stars are blinking with blue, red and yellow colors.”

 

A graduate of the Institute of Physics and Technology in Moscow, Kordan travels the world in search of the most photogenic landscapes, and judging by his portfolio as well as his increasingly popular Instagram, he’s had no trouble finding and capturing them.

more at the link...

http://weburbanist.com/2016/08/08/floating-in-space-milky-way-reflections-on-mirror-like-salt-flats/

 

milky-way-2-960x641.jpg

credit  Daniel Kordan

 

 

 

milky-way-1-644x430.jpg

credit Daniel Kordan

 

 

 

milky-way-5-644x415.jpg

credit Daniel Kordan

 

:woot:

  • Like 2
  • 4 weeks later...

ALMA finds unexpected trove of gas around larger stars

 

122601_web.jpg

Artist impression of a debris disk surrounding a star in the Scorpius-Centaurus Association. ALMA discovered that -- contrary to expectations -- the more massive stars in this region retain considerable stores of carbon monoxide gas. This finding could offer new insights into the timeline for giant planet formation around young stars.
CREDIT
NRAO/AUI/NSF; D. Berry / SkyWorks

 

Quote

Astronomers using the Atacama Large Millimeter/submillimeter Array (ALMA) surveyed dozens of young stars -- some Sun-like and others approximately double that size -- and discovered that the larger variety have surprisingly rich reservoirs of carbon monoxide gas in their debris disks. In contrast, the lower-mass, Sun-like stars have debris disks that are virtually gas-free.

 

This finding runs counter to astronomers' expectations, which hold that stronger radiation from larger stars should strip away gas from their debris disks faster than the comparatively mild radiation from smaller stars. It may also offer new insights into the timeline for giant planet formation around young stars.

 

Debris disks are found around stars that have shed their dusty, gas-filled protoplanetary disks and gone on to form planets, asteroids, comets, and other planetesimals. Around younger stars, however, many of these newly formed objects have yet to settle into stately orbits and routinely collide, producing enough rubble to spawn a "second-generation" disk of debris.

 

"Previous spectroscopic measurements of debris disks revealed that certain ones had an unexpected chemical signature suggesting they had an overabundance of carbon monoxide gas," said Jesse Lieman-Sifry, lead author on a paper published in Astrophysical Journal. At the time of the observations, Lieman-Sifry was an undergraduate astronomy major at Wesleyan University in Middletown, Connecticut. "This discovery was puzzling since astronomers believe that this gas should be long gone by the time we see evidence of a debris disk," he said.

 

Quote

The existence of this gas may have important implications for planet formation, says Hughes. Carbon monoxide is a major constituent of the atmospheres of giant planets. Its presence in debris disks could mean that other gases, including hydrogen, are present, but perhaps in much lower concentrations. If certain debris disks are able to hold onto appreciable amounts of gas, it might push back astronomers' expected deadline for giant planet formation around young stars, the astronomers speculate.

 

"Future high-resolution observations of these gas-rich systems may allow astronomers to infer the location of the gas within the disk, which may shed light on the origin of the gas," says co-author Antonio Hales, an astronomer with the Joint ALMA Observatory in Santiago, Chile, and the National Radio Astronomy Observatory in Charlottesville, Virginia. "For instance, if the gas was produced by planetesimal collisions, it should be more highly concentrated in regions of the disk where those impacts occurred. ALMA is the only instrument capable of making these kind of high-resolution images."

 

According to Lieman-Sifry, these dusty disks are just as diverse as the planetary systems they accompany. The discovery that the debris disks around some larger stars retain carbon monoxide longer than their Sun-like counterparts may provide insights into the role this gas plays in the development of planetary systems.

http://www.eurekalert.org/pub_releases/2016-08/nrao-afu082516.php

 

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

 

Cosmic Microwave Background: Remnant of the Big Bang

 

2014-tkp-astro-explained.jpg?interpolati

An image of the cosmic microwave background radiation, taken by the European Space Agency (ESA)'s Planck satellite in 2013, shows the small variations across the sky
Credit: ESA/Planck Collaboration

 

Quote

The cosmic microwave background (CMB) is thought to be leftover radiation from the Big Bang, or the time when the universe began. As the theory goes, when the universe was born it underwent a rapid inflation and expansion. (The universe is still expanding today, and accelerating for unknown reasons). The CMB represents the heat left over from the Big Bang.

 

You can't see the CMB with your naked eye, but it is everywhere in the universe. It is invisible to humans because it is so cold, just 2.725 degrees above absolute zero (minus 459.67 degrees Fahrenheit, or minus 273.15 degrees Celsius.) This means its radiation is most visible in the microwave part of the electromagnetic spectrum.

 

Origins and discovery

The universe began 13.7 billion years ago, and the CMB dates back to about 400,000 years after the Big Bang. That's because in the early stages of the universe, when it was just one-hundred-millionth the size it is today, its temperature was extreme: 273 million degrees above absolute zero, according to NASA. 

 

Any atoms present at that time were quickly broken apart into small particles (protons and electrons). The radiation from the CMB in photons (particles representing quantums of light, or other radiation) was scattered off the electrons. “Thus, photons wandered through the early universe, just as optical light wanders through a dense fog,” NASA wrote.

 

About 380,000 years after the Big Bang, the universe was cool enough that hydrogen could form. Because the CMB photons are barely affected by hitting hydrogen, the photons travel in straight lines. Cosmologists refer to a “surface of last scattering” when the CMB photons last hit matter; after that, the universe was too big. So when we map the CMB, we are looking back in time to 380,000 years after the Big Bang, just after the universe was opaque to radiation.

http://www.space.com/33892-cosmic-microwave-background.html

 

Those of you reading this post are more than aware of the CMB, but I saw this article and wanted to put up links to various full size HD images for your viewing...

 

WMAP map types

http://wmap.gsfc.nasa.gov/resources/cmbimages.html

 

9 year image sizes available...white or black backgrounds as well...

http://wmap.gsfc.nasa.gov/media/121238/index.html

 

ilc_9yr_moll4096.png

 

 

I still think there's something we are missing when it comes to the CMB and all that relates to it. Obviously it explains the Big Bang (or at least what we think of as the Big Bang) in fairly accurate terms and nails down almost exactly when the universe became opaque to the CMB photons. I just feel there's something staring us in the face, literally and we are missing it.

  • Like 2

Here's food for thought

 

"Every Black Hole Contains a New Universe"

 

https://www.insidescience.org/news/every-black-hole-contains-new-universe

 

Consider that the CMB is the thermal variations in the event horizon of our black hole universe.

 

Or not.

Yeah I've read articles about that and the whole CMB thermal variations are because its literally the event horizon of our black hole universe. Some of it is explained by this, a lot of it is not however. Like all good science, we are driven to find the answers to these questions.

  • Like 2
44 minutes ago, DocM said:

Here's food for thought

 

"Every Black Hole Contains a New Universe"

 

https://www.insidescience.org/news/every-black-hole-contains-new-universe

 

Consider that the CMB is the thermal variations in the event horizon of our black hole universe.

 

Or not.

I also think it's safe to say that while like a black whole, it is likely not an actual black hole (as many of the commenters seem to think it is). Different phenomena can have similar characteristics. Regardless, it is an elegant explanation of the behavior we're observing.

  • Like 2

NASA Extends Contract for Hubble Space Telescope Mission Operations

 

Quote

NASA has awarded a contract extension to Lockheed Martin Space Systems Corporation (LMSSC) of Greenbelt, Maryland, to continue maintaining the health and safety of the agency's Hubble Space Telescope observatory through the next phase of its science mission.

 

Mission Operations, Systems Engineering, and Software (MOSES) II is a cost-plus-fixed-fee, sole source extension valued at approximately $114.3 million, with a performance period that ends June 30, 2021.

 

Under this contract, LMSSC will conduct all non-science elements of Hubble operations to ensure safe and efficient control and utilization of the space observatory, maintenance and operation of Hubble-unique facilities and equipment, and creation, maintenance, and utilization of Hubble operations processes and procedures.

 

The contractor also will perform systems engineering tasks required to properly maintain the space observatory's flight and ground systems, including optimizing mission system capabilities to maximize Hubble operations effectiveness and science productivity.

http://www.spacedaily.com/reports/NASA_Extends_Contract_for_Hubble_Space_Telescope_Mission_Operations_999.html

 

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

 

Record-Breaking Galaxy Cluster Discovered

 

clj1001_w11.jpg

Image courtesy X-ray: NASA/CXC/Universite Paris/T.Wang et al; Infrared: ESO/UltraVISTA; Radio: ESO/NAOJ/NRAO/ALMA.

 

Quote

A new record for the most distant galaxy cluster has been set using NASA's Chandra X-ray Observatory and other telescopes. This galaxy cluster may have been caught right after birth, a brief, but important stage of evolution never seen before.

 

The galaxy cluster is called CL J1001+0220 (CL J1001 for short) and is located about 11.1 billion light-years from Earth. The discovery of this object pushes back the formation time of galaxy clusters - the largest structures in the universe held together by gravity - by about 700 million years.

 

"This galaxy cluster isn't just remarkable for its distance, it's also going through an amazing growth spurt unlike any we've ever seen," said Tao Wang of the French Alternative Energies and Atomic Energy Commission (CEA) who led the study.

 

The core of CL J1001 contains eleven massive galaxies - nine of which are experiencing an impressive baby boom of stars. Specifically, stars are forming in the cluster's core at a rate that is equivalent to over 3,000 Suns forming per year, a remarkably high value for a galaxy cluster, including those that are almost as distant, and therefore as young, as CL J1001.

 

The diffuse X-ray emission detected by Chandra and ESA's XMM-Newton Observatory comes from a large amount of hot gas, one of the defining features of a true galaxy cluster.

 

"It appears that we have captured this galaxy cluster at a critical stage just as it has shifted from a loose collection of galaxies into a young, but fully formed galaxy cluster," said co-author David Elbaz from CEA.

 

Previously, only these loose collections of galaxies, known as protoclusters, had been seen at greater distances than CL J1001.

http://www.spacedaily.com/reports/Record_Breaking_Galaxy_Cluster_Discovered_999.html

 

CHANDRA X-Ray Observatory

http://chandra.si.edu/photo/2016/clj1001/

 

clj1001_w55.jpg

Radio image

 

clj1001_w44.jpg

Infrared image

 

 

clj1001_w22.jpg

X-ray image

 

 

clj1001_w11.jpg

Composite image from above images.

 

:)

  • Like 3

Young Magnetar Likely the Slowest Pulsar Ever Detected

 

rcw103_0.jpg?itok=cjnbdruv

RCW 103: Young Magnetar    credit NASA/Chandra

 

Quote

Using NASA’s Chandra X-ray Observatory and other X-ray observatories, astronomers have found evidence for what is likely one of the most extreme pulsars, or rotating neutron stars, ever detected. The source exhibits properties of a highly magnetized neutron star, or magnetar, yet its deduced spin period is thousands of times longer than any pulsar ever observed.

 

For decades, astronomers have known there is a dense, compact source at the center of RCW 103, the remains of a supernova explosion located about 9,000 light years from Earth.  This composite image shows RCW 103 and its central source, known officially as 1E 161348-5055 (1E 1613, for short), in three bands of X-ray light detected by Chandra. In this image, the lowest energy X-rays from Chandra are red, the medium band is green, and the highest energy X-rays are blue. The bright blue X-ray source in the middle of RCW 103 is 1E 1613. The X-ray data have been combined with an optical image from the Digitized Sky Survey.

 

Observers had previously agreed that 1E 1613 is a neutron star, an extremely dense star created by the supernova that produced RCW 103. However, the regular variation in the X-ray brightness of the source, with a period of about six and a half hours, presented a puzzle.  All proposed models had problems explaining this slow periodicity, but the main ideas were of either a spinning neutron star that is rotating extremely slowly because of an unexplained slow-down mechanism, or a faster-spinning neutron star that is in orbit with a normal star in a binary system.

 

On June 22, 2016, an instrument aboard NASA’s Swift telescope captured the release of a short burst of X-rays from 1E 1613. The Swift detection caught astronomers’ attention because the source exhibited intense, extremely rapid fluctuations on a time scale of milliseconds, similar to other known magnetars. These exotic objects possess the most powerful magnetic fields in the Universe –trillions of times that observed on the Sun – and can erupt with enormous amounts of energy.

 

Seeking to investigate further, a team of astronomers led by Nanda Rea of the University of Amsterdam quickly asked two other orbiting telescopes – NASA’s Chandra X-ray Observatory and Nuclear Spectroscopic Telescope Array, or NuSTAR – to follow up with observations.

 

New data from this trio of high-energy telescopes, and archival data from Chandra, Swift and ESA’s XMM-Newton confirmed that 1E 1613 has the properties of a magnetar, making it only the 30th known. These properties include the relative amounts of X-rays produced at different energies and the way the neutron star cooled after the 2016 burst and another burst seen in 1999. The binary explanation is considered unlikely because the new data show that the strength of the periodic variation in X-rays changes dramatically both with the energy of the X-rays and with time. However, this behavior is typical for magnetars.

 

But the mystery of the slow spin remained. The source is rotating once every 24,000 seconds (6.67 hours), much slower than the slowest magnetars known until now, which spin around once every 10 seconds. This would make it the slowest spinning neutron star ever detected.

 

Astronomers expect that a single neutron star will be spinning quickly after its birth in the supernova explosion and will then slow down over time as it loses energy. However, the researchers estimate that the magnetar within RCW 103 is about 2,000 years old, which is not enough time for the pulsar to slow down to a period of 24,000 seconds by conventional means.

 

While it is still unclear why 1E 1613 is spinning so slowly, scientists do have some ideas. One leading scenario is that debris from the exploded star has fallen back onto magnetic field lines around the spinning neutron star, causing it to spin more slowly with time. Searches are currently being made for other very slowly spinning magnetars to study this idea in more detail.

 

Another group, led by Antonino D'Aì at the National Institute of Astrophysics (INAF) in Palermo, Italy, monitored 1E 1613 in X-rays using Swift and in the near-infrared and visible light using the 2.2-meter telescope at the European Southern Observatory at La Silla, Chile, to search for any low-energy counterpart to the X-ray burst. They also conclude that 1E 1613 is a magnetar with a very slow spin period.

http://www.nasa.gov/mission_pages/chandra/young-magnetar-likely-the-slowest-pulsar-ever-detected.html

 

 

Papers

Magnetar-like activity from the central compact object in the SNR RCW103

 

Evidence for the magnetar nature of 1E 161348-5055 in RCW 103

 

 

Website, Chandra

http://chandra.harvard.edu/photo/2016/rcw103/

 

rcw103_w33.jpg

Optical image

 

 

rcw103_w22.jpg

X-ray image

 

 

rcw103_w11.jpg

Composite image

 

:)

  • Like 3

1 Billion Stars Mapped! Most Detailed Catalog of Milky Way Is Revealed

 

Quote

The most detailed 3D map yet of a billion stars in the Milky Way galaxy was released today (Sept. 14), along with a sneak peek at brand-new data on millions of stars collected by the European Space Agency's Gaia spacecraft.

 

Gaia has been scanning the sky to create a catalog of more than a billion stars in and around the Milky Way since 2014. Today's first data release includes precise positions and brightness of 1.142 billion stars, plus distances and motions of more than 2 million stars. ESA scientists used the observations to create this stunning fly-through of a packed star cluster.

 

Just 14 months into its 5-year mission, Gaia's data release is only the beginning of loads of new information about our galaxy that Gaia is expected to produce. The mission will ultimately build the most comprehensive, detailed and accurate star catalog of all time.

 

gaia-galaxy-map.jpg?1473882453?interpola

This all-sky view of the stars in our Milky Way galaxy, as well as neighboring galaxies, take center stage in this sky map by the European Space Agency's Gaia satellite during its first year of operation.
Credit: ESA/Gaia/DPAC

Image link

 

Quote

While this may be the biggest and most ambitious galaxy-mapping endeavor yet, the vast amount of stars observed in this mission will represent only about 1 percent of all of the stars in the Milky Way galaxy.

http://www.space.com/34068-gaia-star-map-first-data-released.html?utm_source=Twitter&utm_medium=Twitter&utm_campaign=socialtwitterspc&cmpid=social_spc_514648

 

http://www.esa.int/Our_Activities/Space_Science/Gaia/Gaia_s_billion-star_map_hints_at_treasures_to_come

 

 

Gaia-first-sky-map-annotated.jpg?1473878

An annotated version of Gaia's first map of all of the stars in and around the Milky Way galaxy.
Credit: ESA / Gaia / DPAC

image link

 

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

 

ESA Has Added 1.1 Billion Stars to Its Milky Way Map. Space News.

video is 2:40 min.

 

 

 

Two million stars mapped by ESA's Gaia satellite

video is 1:13 min.

 

 

 

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

 

Astronomy & Astrophysics papers on GAIA

 

GAIA Overview

http://www.esa.int/Our_Activities/Space_Science/Gaia/Gaia_overview

 

:)

  • 2 weeks later...

Hubble Views a Colorful Demise of a Sun-like Star

 

heic0703a.jpg?itok=a-0i5vh4

Credits: NASA, ESA, and K. Noll (STScI), Acknowledgment: The Hubble Heritage Team (STScI/AURA)

 

Quote

This image, taken by the NASA/ESA Hubble Space Telescope, shows the colorful "last hurrah" of a star like our sun. The star is ending its life by casting off its outer layers of gas, which formed a cocoon around the star's remaining core. Ultraviolet light from the dying star makes the material glow. The burned-out star, called a white dwarf, is the white dot in the center. Our sun will eventually burn out and shroud itself with stellar debris, but not for another 5 billion years.


Our Milky Way Galaxy is littered with these stellar relics, called planetary nebulae. The objects have nothing to do with planets. Eighteenth- and nineteenth-century astronomers called them the name because through small telescopes they resembled the disks of the distant planets Uranus and Neptune. The planetary nebula in this image is called NGC 2440. The white dwarf at the center of NGC 2440 is one of the hottest known, with a surface temperature of more than 360,000 degrees Fahrenheit (200,000 degrees Celsius). The nebula's chaotic structure suggests that the star shed its mass episodically. During each outburst, the star expelled material in a different direction. This can be seen in the two bowtie-shaped lobes. The nebula also is rich in clouds of dust, some of which form long, dark streaks pointing away from the star. NGC 2440 lies about 4,000 light-years from Earth in the direction of the constellation Puppis.


The material expelled by the star glows with different colors depending on its composition, its density and how close it is to the hot central star. Blue samples helium; blue-green oxygen, and red nitrogen and hydrogen. 

http://www.nasa.gov/image-feature/goddard/2016/hubble-views-a-colorful-demise-of-a-sun-like-star

 

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

 

ALMA Explores the Hubble Ultra Deep Field: Uncovers Insights into 'Golden Age' of Galaxy Formation

 

Quote

International teams of astronomers, using the Atacama Large Millimeter/submillimeter Array (ALMA), have explored the same distant corner of the Universe first revealed in the iconic image of the Hubble Ultra Deep Field (HUDF).

 

The new ALMA observations, which are significantly deeper and sharper than previous surveys at millimeter wavelengths, trace the previously unknown abundance of star-forming gas at different points in time, providing new insights into the "Golden Age" of galaxy formation approximately 10 billion years ago.

 

The researchers presented their findings today at the Half a Decade of ALMA Conference in Palm Springs, California. The results are also accepted for publication in a series of seven scientific papers appearing in the Astrophysical Journal and one in the Monthly Notices of the Royal Astronomical Society.

 

Just like the pioneering deep-field observations with the NASA/ESA Hubble Space Telescope, scientists using ALMA surveyed a seemingly unremarkable section of the Cosmos in a so-called “blind search”. This type of observation probes a specific region of space to see what can be discovered serendipitously rather than homing in on a predetermined target, like an individual galaxy or star-forming nebula.

 

"We conducted the first fully blind, three-dimensional search for cool gas in the early Universe," said Chris Carilli, an astronomer with the National Radio Astronomy Observatory (NRAO) in Socorro, New Mexico, and member of one of the research teams. "Through this, we discovered a population of galaxies that is not clearly evident in any other deep surveys of the sky."

 

160922_nrao16cb09c_nrao.jpg

ALMA surveyed the Hubble Ultra Deep Field, uncovering new details of the star-forming history of the Universe. This close-up image reveals one such galaxy (orange), rich in carbon monoxide, showing it is primed for star formation. The blue features are galaxies imaged by Hubble. B. Saxton (NRAO/AUI/NSF); ALMA (ESO/NAOJ/NRAO); NASA/ESA Hubble

 

Quote

Unlike Hubble, which studies visible and infrared light from bright cosmic objects like stars and galaxies, ALMA studies the faint millimeter-wavelength light emitted by cold gas and dust, the raw material of star formation. ALMA's ability to see a completely different portion of the electromagnetic spectrum allows astronomers to study a different class of astronomical objects, such as massive star-forming clouds and protoplanetary disks, as well as objects that are too faint to observe in visible light.

 

Jim Dunlop, lead author of one of the teams sums up its importance: “This is a breakthrough result. For the first time we are properly connecting the visible and ultraviolet light view of the distant Universe from Hubble and far-infrared/millimeter views of the Universe from ALMA.”

 

The new ALMA observations were specifically tailored to detect galaxies that are rich in carbon monoxide (CO), a tracer molecule that identifies regions rich in molecular gas and primed for star formation. Even though these molecular gas reservoirs give rise to star formation in galaxies, they are invisible to Hubble. ALMA can therefore reveal the "missing half" of the galaxy formation and evolution process.

 

160922_nrao16cb09a_nrao.jpg

A trove of galaxies, rich in dust and cold (indicating star-forming potential) was imaged by ALMA (orange) in the Hubble Ultra Deep Field. Credit: B. Saxton (NRAO/AUI/NSF); ALMA (ESO/NAOJ/NRAO); NASA/ESA Hubble

 

Quote

"These newly detected carbon-monoxide rich galaxies represent a substantial contribution to the star-formation history of the Universe," said Roberto Decarli, an astronomer with the Max Planck Institute for Astronomy (MPIA) in Heidelberg, Germany, and member of the research team.

 

"With ALMA we have opened a pathway for studying the early formation and assembly of galaxies in the Hubble Ultra Deep Field."

 

The new ALMA observations of the HUDF include two distinct, yet complementary types of data: continuum observations, which reveal dust emission and star formation, and a spectral line survey, which looks at the cold molecular gas fueling star formation. The line survey is particularly valuable because it includes information about the degree to which light from distant objects has been redshifted by the expansion of the Universe. Greater redshift means that an object is further away and seen farther back in time.

 

160922_nrao16cb09d.jpg

Looking back through cosmic time in the Hubble Ultra Deep Field, ALMA traced the presence of carbon monoxide gas. This enabled astronomers to create a 3-D image of the star-forming potential of the Cosmos. Credit: R. Decarli (MPIA); ALMA (ESO/NAOJ/NRAO)

 

Quote

With the most recent observations, astronomers were able to create a three-dimensional map of star-forming gas as it evolves over cosmic time, from the present to about two billion years after the Big Bang.

 

"The new ALMA results imply a rapidly rising gas content in galaxies with increasing look-back time," said Manuel Aravena, an astronomer with the Diego Portales University in Santiago, Chile, and member of the research team. "This increasing gas content is likely the root cause for the remarkable increase in star formation rates during the peak epoch of galaxy formation, some 10 billion years ago."

research papers at the link...

http://www.almaobservatory.org/en/press-room/press-releases/1040-alma-explores-the-hubble-ultra-deep-field-uncovers-insights-into-golden-age-of-galaxy-formation

 

:)

  • Like 3

China's large radio telescope begins operations


 

Quote

The world's largest radio telescope has began operating in southwestern China, a project which Beijing says will help humanity search for alien life.

 

The mega telescope began working around noon, the official Xinhua news agency reported on Sunday, adding that it will explore space and search for signs of intelligent life.

 

The 1.2 billion yuan ($180 million) science mega-project is named after its huge dimensions: the Five-hundred-metre Aperture Spherical Telescope, or FAST.

 

Built within a valley surrounded by naturally-formed karst hills in China's remote and mountainous southwestern Guizhou province, the FAST radio telescope's huge dish is equal in size to 30 football pitches and was built from 4,000 individual metal panels.

 

It also required the relocation of 10,000 people living in the vicinity of the huge structure.

 

The feasibility study for the telescope was carried out over 14 years and construction took more than five years to complete.

 

/snip

 

 

 

More at Al Jazeera

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