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Crowdsourcing The Cosmos: Astronomers Welcome All To Identify Star Clusters In Andromeda Galaxy

December 8, 2012 Leave a comment

Credit: Robert Gendler

Credit: Robert Gendler

Astronomers are inviting the public to search Hubble Space Telescope images of the Andromeda galaxy to help identify star clusters and increase understanding of how galaxies evolve.

The new Andromeda Project, set to study thousands of high-resolution Hubble images, is a collaboration among scientists at the University of Washington, the University of Utah and several other partners.

“It’s an amazing opportunity to discover something new,” said Julianne Dalcanton, UW astronomy professor. “Anyone can look at these beautiful Hubble images and participate in the scientific process. And it’s a huge help to us.”

Full Story: http://www.washington.edu/news/2012/12/04/crowdsourcing-the-cosmos-astronomers-welcome-all-to-identify-star-clusters-in-andromeda-galaxy/
Also: http://unews.utah.edu/news_releases/andromeda-wants-you/

WIYN/NOAO: The Bubble Nebula, Observed With The New One Degree Imager Camera

December 8, 2012 Leave a comment

Credit: T.A. Rector (University of Alaska Anchorage), WIYN ODI team & WIYN/NOAO/AURA/NSF

Credit: T.A. Rector (University of Alaska Anchorage), WIYN ODI team & WIYN/NOAO/AURA/NSF

Just in time for the holidays, a spectacular image of the Bubble Nebula (NGC 7635) demonstrates the potential of the new camera known as the One Degree Imager, or ODI, that is being commissioned at the WIYN 3.5-meter telescope on Kitt Peak. The Bubble Nebula is a shell of gas and dust carved out by the stellar wind of the massive central star (BD+60 2522), and ionized by the same star’s high-energy light. Located in the constellation Cassiopeia, this nebula is about 10 light-years across.

The accompanying wide field of the Bubble Nebula covers an area of the sky of 25 by 25 arc minutes, just a little smaller than the full moon. The exquisite resolution, or sharpness, of the stars right to the edge of the image is a hint of things to come.

Full Story: http://www.noao.edu/news/2012/pr1207.php

Image Of The Carina Nebula Marks Inauguration Of VLT Survey Telescope

December 8, 2012 Leave a comment

Credit: ESO. Acknowledgement: VPHAS+ Consortium/Cambridge Astronomical Survey Unit

Credit: ESO. Acknowledgement: VPHAS+ Consortium/Cambridge Astronomical Survey Unit

A spectacular new image of the star-forming Carina Nebula has been captured by the VLT Survey Telescope at ESO’s Paranal Observatory and released on the occasion of the inauguration of the telescope in Naples today.

The VST is a state-of-the-art 2.6-metre telescope, with the huge 268-megapixel camera OmegaCAM at its heart. It is designed to map the sky both quickly and with very fine image quality. The VST is a joint venture between ESO and INAF and OmegaCam has been provided by the OmegaCam consortium. This new telescope is the largest telescope in the world exclusively dedicated to surveying the sky at visible wavelengths. The occasion of the inauguration has been marked by the release of a dramatic picture of the Carina Nebula taken with the new telescope.

This star formation region is one of the most prominent and frequently imaged objects of the southern sky. It has been the subject of many earlier images with ESO telescopes. However, the glowing gas cloud is huge and it is difficult for most large telescopes to study more than a tiny part of it at once. This makes it an ideal target for the VLT Survey Telescope and its big camera, OmegaCAM. The VST delivers very sharp images because of its high quality optics and the excellent site. But, as it was designed for surveys of the sky, it also has a very wide field of view that can take in almost all of the Carina Nebula in a single picture.

Full Story: http://www.eso.org/public/news/eso1250/

Vast Systems Of Ancient Caverns On Mars May Have Captured Enormous Floodwaters

December 8, 2012 Leave a comment

An international research team led by the Planetary Science Institute has found evidence that indicates that approximately 2 billion years ago enormous volumes of catastrophic floods discharges may have been captured by extensive systems of caverns on Mars, said PSI Research Scientist, J. Alexis Palmero Rodriguez.

Rodriguez and the research team came to this conclusion after studying the terminal regions of the Hebrus Valles, an outflow channel that extends approximately 250 kilometers downstream from two zones of surface collapse.

The Martian outflow channels comprise some of the largest known channels in the solar system. Although it has been proposed their discharge history may have once led to the formation of oceans, the ultimate fate and nature of the fluid discharges has remained a mystery for more than 40 years, and their excavation has been attributed to surface erosion by glaciers, debris flows, catastrophic floodwaters, and perhaps even lava flows, Rodriguez said.

Full Story: http://www.psi.edu/news/press-releases

Hubble Sees A Galaxy Hit A Bullseye

December 8, 2012 Leave a comment

 

Hubble view of NGC 922. Credit: NASA, ESA

Hubble view of NGC 922. Credit: NASA, ESA

NGC 922’s current unusual form is a result of a cosmic bullseye millions of years ago. A smaller galaxy, catalogued as 2MASXI J0224301-244443, plunged right through the heart of NGC 922 and shot out the other side. In wide-field views of the NGC 922, the small interloper can be still be seen shooting away from the scene of the crash.

As the small galaxy passed through the middle of NGC 922, it set up ripples that disrupted the clouds of gas, and triggered the formation of new stars whose radiation then lit up the remaining gas. The bright pink colour of the resulting nebulae is a characteristic sign of this process, and it is caused by excited hydrogen gas (the dominant element in interstellar gas clouds). This process of excitation and emission of light by gases is similar to that in neon signs.

In theory, if two galaxies are aligned just right, with the small one passing through the centre of the larger one, the ring of nebulae should form a perfect circle, but more often the two galaxies are slightly off kilter, leading to a circle that, like this one, is noticeably brighter on one side than the other.

Full Story: http://www.spacetelescope.org/news/heic1218/

Astronomers Go Infrared To Map Brightest Galaxies In Universe

December 8, 2012 Leave a comment

A group of astronomers from the University of Hawaii at Manoa, the U.S. Mainland, Canada, and Europe recently used the twin telescopes of the W. M. Keck Observatory on Mauna Kea, Hawaii, to conduct a census of the brightest, but until now unseen, galaxies in the distant Universe, bringing astronomers one step closer to understanding how galaxies form and evolve.

These galaxies glow so brightly at infrared wavelengths that they would outshine our own Milky Way by hundreds, maybe thousands, of times. They are forming stars so quickly that between 100 and 500 new stars are born in each galaxy every year, and have been coined “starbursts” by astronomers.

While it’s not clear what gives these galaxies their intense luminosity, it could be the result of a collision between two spiral-type galaxies, similar to the Milky Way and Andromeda Galaxies. Or they could be in a particularly gas-rich region of space, where galaxies form stars quickly due to constant bombardment from gas and dust.

Despite their brightness, these galaxies are nearly invisible at the wavelengths our eyes and most telescopes on Earth can see because they contain huge amounts of dust, which absorbs visible starlight. But they were detectable directly in the infrared from observations at the Herschel Space Observatory, said Dr. Caitlin Casey, a Hubble fellow at the UH Manoa Institute for Astronomy and the lead scientist behind the new results. “Herschel is an infrared space telescope sensitive to wavelengths not observable from within Earth’s atmosphere,” she said.

Full Story: http://keckobservatory.org/news/astronomers_go_infrared_to_map_brightest_galaxies_in_universe
Also: http://www.esa.int/esaSC/SEMXN4F16AH_index_0.html
Also: http://sci.esa.int/science-e/www/object/index.cfm?fobjectid=51199

Titan, Saturn’s Largest Moon, Icier Than Thought, Say Stanford Scientists

December 8, 2012 Leave a comment

A new analysis of topographic and gravity data from Titan, the largest of Saturn’s moons, indicates that Titan’s icy outer crust is twice as thick as has generally been thought.

Scientists have long suspected that a vast ocean of liquid water lies under the crust. The new study suggests that the internally generated heat that keeps that ocean from freezing solid depends far more on Titan’s interactions with Saturn and its other moons than had been suspected.

Titan has long intrigued scientists because of its similarities to the Earth. Like Earth, Titan appears to have a layered structure, crudely similar to the concentric layers of an onion, albeit far less edible. “Titan probably has a core that is a mixture of ice and rock,” said Howard Zebker, a professor of geophysics and of electrical engineering at Stanford University. The core is overlain by the ocean and icy crust.

Full Story: http://news.stanford.edu/pr/2012/pr-titan-saturn-moon-120312.html

Astronomers Discover And “Weigh” Infant Solar System

December 8, 2012 Leave a comment

Astronomers have found the youngest still-forming solar system yet seen, an infant star surrounded by a swirling disk of dust and gas more than 450 light-years from Earth in the constellation Taurus.

The star currently has about one-fifth the mass of the Sun, but, the scientists say, will likely pull in material from its surroundings to eventually match the Sun’s mass. The disk surrounding the young star contains at least enough mass to make seven Jupiters, the largest planet in our Solar System.

“This very young object has all the elements of a solar system in the making,” said John Tobin, of the National Radio Astronomy Observatory. Tobin and his colleagues used the Submillimeter Array and the Combined Array for Millimeter-wave Astronomy to study the object, called L1527 IRS, residing in a stellar nursery called the Taurus Cloud.

Full Story: http://www.nrao.edu/pr/2012/youngsystem/

Galaxy-Wide Echoes From The Past

December 8, 2012 Leave a comment

The green bean galaxy J2240. Credit: CFHT/ESO/M. Schirmer

The green bean galaxy J2240. Credit: CFHT/ESO/M. Schirmer

A new galaxy class has been identified using observations from ESO’s Very Large Telescope (VLT), the Gemini South telescope, and the Canada-France-Hawaii Telescope (CFHT). Nicknamed “green bean galaxies” because of their unusual appearance, these galaxies glow in the intense light emitted from the surroundings of monster black holes and are amongst the rarest objects in the Universe.

Many galaxies have a giant black hole at their centre that causes the gas around it to glow. However, in the case of green bean galaxies, the entire galaxy is glowing, not just the centre. These new observations reveal the largest and brightest glowing regions ever found, thought to be powered by central black holes that were formerly very active but are now switching off.

Astronomer Mischa Schirmer of the Gemini Observatory had looked at many images of the distant Universe, searching for clusters of galaxies, but when he came across one object in an image from the Canada-France-Hawaii Telescope he was stunned — it looked like a galaxy, but it was bright green. It was unlike any galaxy he had ever seen before, something totally unexpected. He quickly applied to use ESO’s Very Large Telescope to find out what was creating the unusual green glow.

Full Story: http://www.eso.org/public/news/eso1249/

Wide Binary Stars: Long-Distance Stellar Relationships

December 8, 2012 Leave a comment

Our Sun is a single star. This puts it in a minority of stars because most stars are binaries—two stars that orbit each other and are bound together by their mutual gravity. Binaries can be very close, sometimes so close that they actually touch each other. Other pairs are extremely wide, with separations up to a light-year or so.

Now Dr. Bo Reipurth of the Institute for Astronomy, University of Hawaii at Manoa, USA, and Dr. Seppo Mikkola of Tuorla Observatory, University of Turku, Finland, have used computer simulations to come up with a mechanism that accounts for the formation of wide binaries. Most stars are initially formed in small compact multiple systems with two, three or even more stars at the center of a cloud core. When more than two stars are together in a small space, they gravitationally pull on each other in a chaotic dance, where the lightest body is often kicked out to the outskirts of the core for long periods of time before falling back into the fray.

Meanwhile, the remaining stars feed on the gas at the center of the cloud core and grow heftier. Eventually, the runt of the litter gets such a large kick that it may be completely ejected. But in some cases, the kick is not strong enough for the third body to fully escape, and so it is sent out into a very wide orbit.

Full Story: http://www.ifa.hawaii.edu/info/press-releases/WideBinaryStars/