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The Turbulent Lives of Stars

September 16, 2011 Leave a comment

The stars are boiling! The reason is the energy generated in the center of the star that wants to escape. If this does not happen quickly enough, the star starts to ‘boil’ in the outer layers causing vibrations that result in light variations, like in the Sun. Such oscillations have now been discovered by Victoria Antoci and collaborators using the NASA spacecraft Kepler, but in a much hotter star. The scientists publish this in the most recent issue of “Nature”.
Besides the discovery of earth-like planets, astronomy is concerned with research on stellar oscillations, among many other topics. The vibrations cause periodic brightness variations of some stars. Asteroseismology works just like the seismic exploration of the Earth’s interior: the frequencies of seismic waves depend on mass and composition of a body and therefore allow to tomographically reproduce its interior structure.

Full Story: http://medienportal.univie.ac.at/presse/aktuelle-pressemeldungen/detailansicht/artikel/the-turbulent-lives-of-stars/

Dawn Collects a Bounty of Beauty from Vesta

September 16, 2011 Leave a comment

Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

A new video from NASA’s Dawn spacecraft takes us on a flyover journey above the surface of the giant asteroid Vesta.

The data obtained by Dawn’s framing camera, used to produce the visualizations, will help scientists determine the processes that formed Vesta’s striking features. It will also help Dawn mission fans all over the world visualize this mysterious world, which is the second most massive object in the main asteroid belt.

The video, which shows Vesta as seen from Dawn’s perspective, can be viewed at:http://www.jpl.nasa.gov/video/index.cfm?id=1020.

You’ll notice in the video that Vesta is not entirely lit up. There is no light in the high northern latitudes because, like Earth, Vesta has seasons. Currently it is northern winter on Vesta, and the northern polar region is in perpetual darkness. When we view Vesta’s rotation from above the south pole, half is in darkness simply because half of Vesta is in daylight and half is in the darkness of night .

Full Story: http://www.jpl.nasa.gov/news/news.cfm?release=2011-293

Space Station Trio Lands Safely In Kazakhstan

September 16, 2011 Leave a comment

Three International Space Station crew members safely returned to Earth Thursday, Sept. 15, wrapping up a six-month mission of research and exploration.

NASA’s Ron Garan, Expedition 28 commander Andrey Borisenko and flight engineer Alexander Samokutyaev, both of the Russian Federal Space Agency, landed their Soyuz spacecraft in Kazakhstan at 11:59 a.m. EDT (9:59 a.m. in Kazakhstan). The trio, which arrived at the station on April 6, had been scheduled to land on Sept. 8, but that was postponed because of the Aug. 24 loss of the Progress 44 cargo ship.

Full Story: http://www.nasa.gov/home/hqnews/2011/sep/HQ_11-303_Exp_28_landing.html

International Space Station Partners Set Tentative Launch Schedule

September 16, 2011 Leave a comment

NASA and its international partners have agreed to a tentative launch schedule with crew flights to the International Space Station resuming on Nov. 14.

The Space Station Control Board, with representation from all partner agencies, set the schedule after hearing the Russian Federal Space Agency’s findings on the Aug. 24 loss of the Progress 44 cargo craft. The dates may be adjusted to reflect minor changes in vehicle processing timelines.

Full Story: http://www.nasa.gov/home/hqnews/2011/sep/HQ_11-306_Soyuz_RTF.html

Cassini Significant Events 09/07/11 – 09/13/11

September 16, 2011 Leave a comment

The most recent spacecraft telemetry was acquired on September 13 from the Deep Space Network tracking complex at Canberra, Australia. The Cassini spacecraft is in an excellent state of health and with the exception of one science instrument being powered off, all subsystems are operating normally. Information on the present position and speed of the Cassini spacecraft may be found on the “Present Position” page at: http://saturn.jpl.nasa.gov/mission/presentposition

Full Story: http://www.astronews.us/2011-09-16-1546.html

Milky Way’s Spiral Arms Are Product of Intergalactic Collision

September 16, 2011 Leave a comment

Image by Tollerud, Purcell and Bullock/UC Irvine

Image by Tollerud, Purcell and Bullock/UC Irvine

UC Irvine astronomers have shown how the Milky Way galaxy’s iconic spiral arms form, according to research published today in the journal Nature.

A dwarf galaxy named Sagittarius loaded with dark matter has careened twice through our much larger home galaxy in the past two billion years, according to telescope data and detailed simulations, and is lined up to do it again. As the galaxies collide, the force of the impact sends stars streaming from both in long loops.  Those continue to swell with stars and are gradually tugged outward by the Milky Way’s rotation into a familiar ringed arm.

It’s the weighty dark matter from Sagittarius that provided the initial push, the researchers said.

Full Story: http://today.uci.edu/news/2011/09/nr_milkyway_110914.php