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Archive for July 10, 2012

Hubble Unmasks Ghost Galaxies


Astronomers have puzzled over why some puny, extremely faint dwarf galaxies spotted in our Milky Way galaxy’s back yard contain so few stars.

These ghost-like galaxies are thought to be some of the tiniest, oldest, and most pristine galaxies in the universe. They have been discovered over the past decade by astronomers using automated computer techniques to search through the images of the Sloan Digital Sky Survey. But astronomers needed NASA’s Hubble Space Telescope to help solve the mystery of these star-starved galaxies.

Hubble views of three of the small-fry galaxies reveal that their stars share the same birth date. The galaxies all started forming stars more than 13 billion years ago — and then abruptly stopped — all in the first billion years after the universe was born in the big bang.

“These galaxies are all ancient and they’re all the same age, so you know something came down like a guillotine and turned off the star formation at the same time in these galaxies,” said Tom Brown of the Space Telescope Science Institute in Baltimore, Md., the study’s leader. “The most likely explanation is reionization.”

Full Story: http://hubblesite.org/newscenter/archive/releases/2012/26/full/

Also: http://www.nasa.gov/mission_pages/hubble/science/ghost-galaxies.html

Also: http://www.spacetelescope.org/news/heic1211/

Astronomy “Hangouts” Featured In New Google Documentary


Using new technology available through Google+ Hangouts, a group of astronomy enthusiasts have been conducting virtual star parties shared by thousands of people around the world. Their efforts were highlighted in a new documentary presented by Google at their annual developer’s conference, Google I/O, in San Francisco on June 27, 2012.

“We’ve been holding Virtual Star Parties every Sunday night, where we pull together live feeds from multiple telescopes around the world and broadcast them into a live Google+ hangout,” said Fraser Cain, publisher of Universe Today (http://www.universetoday.com/), a popular astronomy and space news website, who instigated the online star parties along with astronomer Dr. Pamela Gay from Southern Illinois University, Edwardsville, and CosmoQuest (http://cosmoquest.org/), a new citizen-science and education project. “We’ve done dozens of them now, showcasing the Moon, the planets, and many deep-sky objects. The response has been overwhelming, as we’ve made it possible for people without telescopes or who have cloudy skies a chance to see the night sky from the comfort of their home.”

Documentary: http://www.youtube.com/watch?v=Agrdjd0nyFo

Cassini Flies High To View Saturn’s Rings Again


It’s been nearly two years since NASA’s Cassini spacecraft has had views like those it is now enjoying of Saturn’s glorious rings. These views are possible again because Cassini has changed the angle at which it orbits Saturn and now regularly passes above and below Saturn’s equatorial plane. Steeply inclined orbits around the Saturn system also allow scientists to get better views of the poles and atmosphere of Saturn and its moons.

Cassini’s recent return of ring images has started to pay off. A group of scientists has restarted the imaging team’s studies of the famous propeller features. These features are actually small, longitudinally limited, orbiting gaps in the rings that are cleared out by objects smaller than known moons but larger than typical ring particles.

“We’re entering a new episode in Cassini’s exploratory voyage through the Saturn system,” said Carolyn Porco, imaging team lead, based at the Space Science Institute, Boulder, Colo. “These new ring results are an early harbinger of great things to come. So watch this space!”

Full Story: http://www.ciclops.org/view.php?id=7234&js=1

Also: http://www.jpl.nasa.gov/news/news.cfm?release=2012-199

Dark Matter Scaffolding Of Universe Detected For The First Time


Scientists have, for the first time, directly detected part of the invisible dark matter skeleton of the universe, where more than half of all matter is believed to reside.

The discovery, led by a University of Michigan physics researcher, confirms a key prediction in the prevailing theory of how the universe’s current web-like structure evolved.

The map of the known universe shows that most galaxies are organized into clusters, but some galaxies are situated along filaments that connect the clusters. Cosmologists have theorized that dark matter undergirds those filaments, which serve as highways of sorts, guiding galaxies toward the gravitational pull of the massive clusters. Dark matter’s contribution had been predicted with computer simulations, and its shape had been roughed out based on the distribution of the galaxies. But no one had directly detected it until now.

Full Story: http://www.ns.umich.edu/new/releases/20623-dark-matter-scaffolding-of-universe-detected-for-the-first-time

Flying Along The Vela Ridge


A beautiful blue butterfly flutters towards a nest of warm dust and gas, above an intricate network of cool filaments in this image of the Vela C region by ESA’s Herschel space observatory.

Vela C is the most massive of the four parts of the Vela complex, a massive star nursery just 2300 light-years from the Sun. It is an ideal natural laboratory for us to study the birth of stars.

Herschel’s far-infrared detectors can spot regions where young high- and low-mass stars have heated dense clumps of gas and dust, where new generations of stars may be born.

Full Story: http://www.esa.int/export/esaSC/SEM0XIJXB4H_index_0.html

Coverage Set For Next International Space Station Crew Launch


NASA Television will provide extensive coverage of prelaunch, launch and docking activities of the next trio of crew members who will fly to the International Space Station.

NASA TV coverage of the Soyuz TMA-05M launch begins at 8:30 p.m. CDT, Saturday, July 14. NASA Flight Engineer Sunita Williams, veteran Soyuz Commander Yuri Malenchenko of the Russian Federal Space Agency and Flight Engineer Akihiko Hoshide of the Japan Aerospace Exploration Agency will launch to the station at 9:40 p.m. (8:40 a.m., July 15 Baikonur time) from the Baikonur Cosmodrome in Kazakhstan.

Full Story: http://www.nasa.gov/home/hqnews/2012/jul/HQ_M12-127_Expedition_32-33_TV_Coverage.html

HI-C Sounding Rocket Mission Has Finest Mirrors Ever Made


On July 11, NASA scientists will launch into space the highest resolution solar telescope ever to observe the solar corona, the million degree outer solar atmosphere. The instrument, called HI-C for High Resolution Coronal Imager, will fly aboard a Black Brant sounding rocket to be launched from the White Sands Missile Range in New Mexico. The mission will have just 620 seconds for its flight, spending about half of that time high enough that Earth’s atmosphere will not block ultraviolet rays from the sun. By looking at a specific range of UV light, HI-C scientists hope to observe fundamental structures on the sun, as narrow as 100 miles across.

The spatial resolution on HI-C is some five times more detailed than the Atmospheric Imaging Assembly (AIA) instrument on the Solar Dynamics Observatory (SDO), that can resolve structures down to 600 miles and currently sends back some of our most stunning and scientifically useful images of the sun. Of course, AIA can see the entire sun at this resolution, while HI-C will focus on an area just one-sixth the width of the sun or 135,000 miles across. Also, AIA observes the sun in ten different wavelengths, while HI-C will observe just one: 193 Angstroms. This wavelength of UV light corresponds to material in the sun at temperatures of 1.5 million Kelvin and that wavelength is typically used to observe material in the corona.

Full Story: http://www.nasa.gov/mission_pages/sunearth/news/HI-C.html