Archive
International Dark Sky Week 14 – 20 April, 2012
Celebrate the stars! Created in 2003 by high-school student Jennifer Barlow, IDSW has grown to become a worldwide event and a key component of Global Astronomy Month. The goals of IDSW are to appreciate the beauty of the night sky and to raise awareness of how poor-quality lighting creates light pollution.
Light pollution is a growing problem. Not only does it have detrimental effects on our views of the night sky, but it also disrupts the natural environment, wastes energy, and has the potential to cause health problems.
Full Story: http://www.darksky.org/idsw
NASA’s WISE Mission Sees Skies Ablaze With Blazars
Image credit: NASA/JPL-Caltech
Astronomers are actively hunting a class of supermassive black holes throughout the universe called blazars thanks to data collected by NASA’s Wide-field Infrared Survey Explorer (WISE). The mission has revealed more than 200 blazars and has the potential to find thousands more.
Blazars are among the most energetic objects in the universe. They consist of supermassive black holes actively “feeding,” or pulling matter onto them, at the cores of giant galaxies. As the matter is dragged toward the supermassive hole, some of the energy is released in the form of jets traveling at nearly the speed of light. Blazars are unique because their jets are pointed directly at us.
“Blazars are extremely rare because it’s not too often that a supermassive black hole’s jet happens to point towards Earth,” said Francesco Massaro of the Kavli Institute for Particle Astrophysics and Cosmology near Palo Alto, Calif., and principal investigator of the research, published in a series of papers in the Astrophysical Journal. “We came up with a crazy idea to use WISE’s infrared observations, which are typically associated with lower-energy phenomena, to spot high-energy blazars, and it worked better than we hoped.”
Full Story: http://www.jpl.nasa.gov/news/news.cfm?release=2012-103
NASA Goddard Engineers Testing Webb Telescope’s OSIM and BIA Instruments
Image Credit: NASA Goddard/Chris Gunn
Several critical items related to NASA’s next-generation James Webb Space Telescope are being tested in the giant thermal vacuum test chamber at NASA’s Goddard Space Flight Center, Greenbelt, Md.
These photos show the OTE (Optical Telescope Element) Simulator or OSIM wrapped in a silver blanket on a platform, being lowered down into a vacuum chamber (called the Space Environment Simulator, or SES) by a crane to be tested to withstand the cold temperatures of space.
The OSIM simulates the Webb telescope for the purposes of testing the science instruments that will fly on the observatory. The OSIM itself will never fly into space, but it is a vital part of the testing program to verify that the science cameras and spectrographs will function as planned.
Full Story: http://www.nasa.gov/topics/technology/features/webb-osim.html
‘Time Machine’ Will Study the Early Universe
A new scientific instrument, a “time machine” of sorts, built by UCLA astronomers and colleagues, will allow scientists to study the earliest galaxies in the universe, which could never be studied before.Full Story: http://newsroom.ucla.edu/portal/ucla/time-machine-will-study-the-early-231810.aspx
Discovery of the Musket Ball Cluster
Image Credits: X-ray: NASA/CXC/UCDavis/W.Dawson et al; Optical: NASA/STScI/UCDavis/W.Dawson et al.
Using a combination of powerful observatories in space and on the ground, astronomers have observed a violent collision between two galaxy clusters in which so-called normal matter has been wrenched apart from dark matterthrough a violent collision between two galaxy clusters.
The newly discovered galaxy cluster is called DLSCL J0916.2+2951. It is similar to the Bullet Cluster, the first system in which the separation of dark and normal matter was observed, but with some important differences. The newly discovered system has been nicknamed the “Musket Ball Cluster” because the cluster collision is older and slower than the Bullet Cluster.
Full Story: http://www.chandra.harvard.edu/photo/2012/musketball/
ALMA Reveals Workings of Nearby Planetary System
A new observatory still under construction has given astronomers a major breakthrough in understanding a nearby planetary system and provided valuable clues about how such systems form and evolve. Astronomers using the Atacama Large Millimeter/submillimeter Array (ALMA) have discovered that planets orbiting the star Fomalhaut must be much smaller than originally thought. This is the first published science result from ALMA in its first period of open observations for astronomers worldwide.
The discovery was made possible by exceptionally sharp ALMA images of a disc, or ring, of dust orbiting Fomalhaut, which lies about 25 light-years from Earth. It helps resolve a controversy among earlier observers of the system. The ALMA images show that both the inner and outer edges of the thin, dusty disc have very sharp edges. That fact, combined with computer simulations, led the scientists to conclude that the dust particles in the disc are kept within the disc by the gravitational effect of two planets — one closer to the star than the disc and one more distant.
Full Story: http://www.eso.org/public/news/eso1216/
12-Billion-Year-Old White Dwarf Only 100 Light-Years Away
A University of Oklahoma assistant professor and colleagues have identified two white dwarf stars considered the oldest and closest known to man. Astronomers identified these 11- to 12-billion-year-old white dwarf stars only 100 light years away from Earth. These stars are the closest known examples of the oldest stars in the Universe forming soon after the Big Bang, according to the OU researcher.
Mukremin Kilic, assistant professor of physics and astronomy in the OU College of Arts and Sciences and lead author on a recently published paper, announced the discovery. Kilic says, “A white dwarf is like a hot stove; once the stove is off, it cools slowly over time. By measuring how cool the stove is, we can tell how long it has been off. The two stars we identified have been cooling for billions of years.”
Full Story: http://www.ou.edu/content/publicaffairs/archives/WhiteDwarfStars.html
Exoplanet Orbits Suggest Solar System Structure Is the Norm
The EXOEarths team (Centro de Astrofísica da Universidade do Porto – CAUP), in collaboration with Geneva University, did a joint analysis of data from the HARPS spectrograph and the Kepler satellite. This analysis revealed that the orbits of other planetary systems are aligned, like in a disk, just like in our own Solar System.
Recently, the HARPS spectrograph and the Kepler satellite made a census of the planetary population around stars like our own, revealing a bounty of planetary systems. A follow-up study lead by members of the EXOEarths team (Centro de Astrofísica da Universidade do Porto – CAUP), in collaboration with Geneva University, did a joint analysis of the data which showed that the planetary orbits in a system are strongly aligned, like in a disk, just as we have in our own solar system.
Full Story: http://www.alphagalileo.org/ViewItem.aspx?ItemId=119192&CultureCode=en
Herschel Spots Comet Massacre Around Nearby Star
Image Credits: ESA/Herschel/PACS/Bram Acke, KU Leuven, Belgium
ESA’s Herschel Space Observatory has studied the dusty belt around the nearby star Fomalhaut. The dust appears to be coming from collisions that destroy up to thousands of icy comets every day.
Fomalhaut is a young star, just a few hundred million years old, and twice as massive as the Sun. Its dust belt was discovered in the 1980s by the IRAS satellite, but Herschel’s new images of the belt show it in much more detail at far-infrared wavelengths than ever before.
Bram Acke, at the University of Leuven in Belgium, and colleagues analysed the Herschel observations and found the dust temperatures in the belt to be between –230 and –170ºC. However, because Fomalhaut is slightly off-centre and closer to the southern side of the belt, the southern side is warmer and brighter than the northern side.
Full Story: http://www.esa.int/export/esaSC/SEM1XBHWP0H_index_0.html
