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Pinpointing Stargazing Sites for More Eyes

October 25, 2011 Leave a comment

Communities across England will have a twinkle in their eye and get a big environmental and educational boost thanks to Dark Sky Discovery– a pioneering new national and regional partnership of astronomy and environmental organisations led by the Science and Technology Facilities Council.

A £176.8k grant, funded by the Big Lottery Fund and awarded through Natural England’s Access to Nature programme, will support a 2-year programme to inspire people of all ages and backgrounds to come together in their local area and enjoy the night sky in a radically new way.

Working with astronomy, environmental and community organisations in every English region, the aim is to involve people in identifying safe, accessible ‘Dark Sky Discovery Sites’ – places in urban and rural areas where they can take part in stimulating stargazing sessions. A series of Dark Sky Discovery Sites has been unveiled in England – and also in Wales and Scotland – illustrating the range of great local spots that people can use for stargazing.

Project Leader Dan Hillier, based at the STFC’s Royal Observatory Edinburgh site, says: “In every community there is somewhere that is the best place to see the stars.  Even in towns and cities, there are places such as local parks where people can enjoy the wonders of the night sky, from planets to meteor showers. This project will find ways of helping people from a whole range of different backgrounds – such as schools, community and special needs groups, to discover the universe that is just beyond their doorstep.”

Full Story: http://www.stfc.ac.uk/News%20and%20Events/37742.aspx

NASA Telescopes Help Solve Ancient Supernova Mystery

October 25, 2011 Leave a comment

Image credit: NASA/ESA/JPL-Caltech/UCLA/CXC/SAO

Image credit: NASA/ESA/JPL-Caltech/UCLA/CXC/SAO

A mystery that began nearly 2,000 years ago, when Chinese astronomers witnessed what would turn out to be an exploding star in the sky, has been solved. New infrared observations from NASA’s Spitzer Space Telescope and Wide-field Infrared Survey Explorer, or WISE, reveal how the first supernova ever recorded occurred and how its shattered remains ultimately spread out to great distances.

The findings show that the stellar explosion took place in a hollowed-out cavity, allowing material expelled by the star to travel much faster and farther than it would have otherwise.

“This supernova remnant got really big, really fast,” said Brian J. Williams, an astronomer at North Carolina State University in Raleigh. Williams is lead author of a new study detailing the findings online in the Astrophysical Journal. “It’s two to three times bigger than we would expect for a supernova that was witnessed exploding nearly 2,000 years ago. Now, we’ve been able to finally pinpoint the cause.”

A new image of the supernova, known as RCW 86, is online at http://go.nasa.gov/pnv6Oy .

Full  Story: http://www.jpl.nasa.gov/news/news.cfm?release=2011-329

Team Discovers Unusual Multi-Planet System with NASA’s Kepler Spacecraft

October 25, 2011 Leave a comment

Credit: Tim Jones/McDonald Obs./UT-Austin

Credit: Tim Jones/McDonald Obs./UT-Austin

A team of researchers led by Bill Cochran, senior research scientist with the University of Texas at Austin McDonald Observatory and co-investigator on NASA’s Kepler Mission, used data from NASA’s Kepler spacecraft to discover an unusual multiple-planet system containing a super-Earth and two Neptune-sized planets orbiting in resonance with each other. The findings were announced today in Nantes, France, at a joint meeting of the American Astronomical Society’s Division of Planetary Science and the European Planetary Science Conference. The research will be published in a special Kepler issue of the Astrophysical Journal Supplement Series in November.

Cochran’s team is announcing three planets orbiting Kepler-18, a star similar to the Sun. Kepler-18 is just 10 percent larger than the Sun and contains 97 percent of the Sun’s mass. It may host more planets than the three announced today.

The planets are designated b, c, and d. All three planets orbit much closer to Kepler-18 than Mercury does to the Sun. Orbiting closest to Kepler-18 with a 3.5-day period, planet b weighs in at about 6.9 times the mass of Earth, and twice Earth’s size. Planet b is considered a “super-Earth.” Planet c has a mass of about 17 Earths, is about 5.5 times Earth’s size, and orbits Kepler-18 in 7.6 days. Planet d weighs in at 16 Earths, at 7 times Earth’s size, and has a 14.9-day orbit. The masses and sizes of c and d qualify them as low-density “Neptune-class” planets.

Full Story: http://mcdonaldobservatory.org/news/releases/2011/1004.html

Galaxy Interactions Help Grow Big Black Holes

October 25, 2011 Leave a comment

Supermassive black holes (SMBH) sit at the center of most galaxies that we observe today. How did they grow to millions or billion times the mass of our Sun? Answers to this question have been elusive for some time although important clues have been uncovered. For instance, SMBHs prefer to reside in the most massive galaxies and the mass of a SMBH is directly related to the mass of stars present in the central region (i.e., bulge) of its host galaxy. It is now thought that such massive galaxies grew in part by mergers and interactions between less massive galaxies. Such violent episodes in the evolution of galaxies have also been invoked to explain how matter is driven to their center that can then grow a SMBH.

A simple test is to determine whether SMBHs are found in greater numbers in galaxies undergoing a merger compared to those in isolation. While this sounds easy enough, astronomers have struggled to effectively carry out this test for some time. This is because the glaring light of an actively growing SMBH, seen observationally as either an active galactic nucleus (AGN) or the more luminous quasar, can outshine their entire host galaxy making it difficult to determine whether they reside in a galaxy undergoing an interaction with another fainter galaxy. Such interactions should distort the shape of the galaxy.

Full Story: http://www.ipmu.jp/node/1156