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Archive for January 11, 2013

NASA Telescopes See Weather Patterns In Brown Dwarf

January 11, 2013 Leave a comment

Artist's illustration. Image credit: NASA/JPL-Caltech

Artist’s illustration. Image credit: NASA/JPL-Caltech

Astronomers using NASA’s Spitzer and Hubble space telescopes have probed the stormy atmosphere of a brown dwarf, creating the most detailed “weather map” yet for this class of cool, star-like orbs. The forecast shows wind-driven, planet-sized clouds enshrouding these strange worlds.

Brown dwarfs form out of condensing gas, as stars do, but lack the mass to fuse hydrogen atoms and produce energy. Instead, these objects, which some call failed stars, are more similar to gas planets with their complex, varied atmospheres. The new research is a stepping-stone toward a better understanding not only of brown dwarfs, but also of the atmospheres of planets beyond our solar system.

“With Hubble and Spitzer, we were able to look at different atmospheric layers of a brown dwarf, similar to the way doctors use medical imaging techniques to study the different tissues in your body,” said Daniel Apai, the principal investigator of the research at the University of Arizona in Tucson, who presented the results at the American Astronomical Society meeting Tuesday in Long Beach, Calif.

Full Story: http://www.jpl.nasa.gov/news/news.php?release=2013-013

SOFIA Spots Recent Starburst In The Milky Way Galaxy’s Center

January 11, 2013 Leave a comment

Credit: NASA/DLR/USRA/DSI/FORCAST Team/Lau et al. 2013

Credit: NASA/DLR/USRA/DSI/FORCAST Team/Lau et al. 2013

Researchers using the Stratospheric Observatory for Infrared Astronomy (SOFIA) have captured new images of a ring of gas and dust seven light-years in diameter surrounding the supermassive black hole at the center of the Milky Way, and of a neighboring cluster of extremely luminous young stars embedded in dust cocoons.

SOFIA is a highly modified Boeing 747SP aircraft carrying a telescope with an effective diameter of 100 inches (2.5 meters) to altitudes as high as 45,000 feet (14 km). The images were obtained during SOFIA flights in 2011 with the Faint Object infraRed Camera for the SOFIA Telescope (FORCAST) instrument built by a team with principal investigator Terry Herter of Cornell.

Full Story/Photos/Posters: http://www.sofia.usra.edu/News/news_2013/01_08_13/index.html

Detecting Dusty Clouds And Stars In Our Galaxy

January 11, 2013 Leave a comment

The center of our Milky Way galaxy is a wondrous place full of huge star clusters, dust clouds, magnetic filaments and a supermassive black hole. But it can be a confusing place, too, posing challenges to astronomers trying to image these exotic features and learn more about where they are located in the galaxy.

Northwestern University’s Farhad Zadeh has discovered a new tool for detecting dusty clouds and stars: simply take a picture using radio waves. He is the first to identify what he calls radio dark clouds and stars. Stars in the early and late phases of their evolution are shrouded by huge dusty envelopes in the form of dust and gas outflows.

“When you see these dark stars or clouds in radio wavelength images, it tells you something very interesting,” Zadeh said. “We immediately know there is a cold gas cloud or dusty star mixing with a hot radiative medium and that an interaction is taking place. Knowing details of these clouds is important because the clouds can produce stars and also provide material for the growth of black holes.”

Full Story: http://www.northwestern.edu/newscenter/stories/2013/01/detecting-dusty-clouds-and-stars-in-our-galaxy.html

Cassini Suggests Icing On A Lake

January 11, 2013 Leave a comment

Image credit: NASA/JPL-Caltech/ASI/Cornell

Image credit: NASA/JPL-Caltech/ASI/Cornell

It’s not exactly icing on a cake, but it could be icing on a lake. A new paper by scientists on NASA’s Cassini mission finds that blocks of hydrocarbon ice might decorate the surface of existing lakes and seas of liquid hydrocarbon on Saturn’s moon Titan. The presence of ice floes might explain some of the mixed readings Cassini has seen in the reflectivity of the surfaces of lakes on Titan.

“One of the most intriguing questions about these lakes and seas is whether they might host an exotic form of life,” said Jonathan Lunine, a paper co-author and Cassini interdisciplinary Titan scientist at Cornell University, Ithaca, N.Y. “And the formation of floating hydrocarbon ice will provide an opportunity for interesting chemistry along the boundary between liquid and solid, a boundary that may have been important in the origin of terrestrial life.”

Titan is the only other body besides Earth in our solar system with stable bodies of liquid on its surface. But while our planet’s cycle of precipitation and evaporation involves water, Titan’s cycle involves hydrocarbons like ethane and methane. Ethane and methane are organic molecules, which scientists think can be building blocks for the more complex chemistry from which life arose. Cassini has seen a vast network of these hydrocarbon seas cover Titan’s northern hemisphere, while a more sporadic set of lakes bejewels the southern hemisphere.

Full Story: http://www.jpl.nasa.gov/news/news.php?release=2013-010&cid=release_2013-010

The Farthest Supernova Yet For Measuring Cosmic History

January 11, 2013 Leave a comment

What if you had a “Wayback Television Set” and could watch an entire month of ancient prehistory unfold before your eyes in real time? David Rubin of the U.S. Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) presented just such a scenario to the American Astronomical Society (AAS) meeting in Long Beach, CA, when he announced the discovery of a striking astronomical object: a Type Ia supernova with a redshift of 1.71 that dates back 10 billion years in time. Labeled SN SCP-0401, the supernova is exceptional for its detailed spectrum and precision color measurement, unprecedented in a supernova so distant.

“This is the most distant supernova anyone has ever found for doing dependable cosmology,” says Rubin, a member of the international Supernova Cosmology Project (SCP) based at Berkeley Lab. “The most important unanswered question we have about the nature of dark energy is whether it varies over time – whether it affects the expansion of the universe differently in different eras. With SN SCP-0401, we have the first example of a well-measured supernova sufficiently far away to study the expansion history of the universe from almost 10 billion years ago.”

Full Story: http://newscenter.lbl.gov/news-releases/2013/01/09/scp0401-farthest-yet/