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UH Observations Result In “All Clear” For Potential Asteroid Impact

January 4, 2013 Leave a comment

Using the Gemini North telescope on Mauna Kea, Hawai‘i a team of astronomers from the University of Hawaii’s Institute for Astronomy (IfA) have confirmed that the chance of asteroid 2011 AG5 impacting Earth in 2040 is no longer a significant risk – prompting a collective sigh-of-relief. Previously, scientists estimated that the risk of this 140-meter-diameter (about the length of two American football fields) asteroid colliding with the Earth was as high as one in 500.

If this object were to collide with the Earth it would have released about 100 megatons of energy, several thousand times more powerful than the atomic bombs that ended World-War II. Statistically, a body of this size could impact the Earth on average every 10,000 years.

Full Story: http://www.gemini.edu/node/11922
Also: http://www.ifa.hawaii.edu/info/press-releases/allclear2011AG5.shtml

WMAP Team Releases Final Results, Based On Nine Years Of Observations

January 4, 2013 Leave a comment

Since its launch in 2001, the Wilkinson Microwave Anisotropy Probe (WMAP) space mission has revolutionized our view of the universe, establishing a cosmological model that explains a widely diverse collection of astronomical observations. Led by Johns Hopkins astrophysicist Charles L. Bennett, the WMAP science team has determined, to a high degree of accuracy and precision, not only the age of the universe, but also the density of atoms; the density of all other non-atomic matter; the epoch when the first stars started to shine; the “lumpiness” of the universe, and how that “lumpiness” depends on scale size.

In short, when used alone (with no other measurements), WMAP observations have made our knowledge of those six parameters above about 68,000 times more precise, thereby converting cosmology from a field of often wild speculation to a precision science.

Now, two years after the probe “retired,” Bennett and the WMAP science team are releasing its final results, based on a full nine years of observations.

“It is almost miraculous, says Bennett, Alumni Centennial Professor of Physics and Astronomy and Johns Hopkins Gilman Scholar at the Johns Hopkins University’s Krieger School of Arts and Sciences. “The universe encoded its autobiography in the microwave patterns we observe across the whole sky. When we decoded it, the universe revealed its history and contents. It is stunning to see everything fall into place.”

Full Story, Results and Links: http://releases.jhu.edu/2012/12/21/wmap-team-releases-final-results-based-on-nine-years-of-observations/

Powerful Supercomputer Makes ALMA A Telescope

January 4, 2013 Leave a comment

One of the most powerful calculating machines known to the civilian world has been installed and tested in a remote, high-altitude site in the Andes Mountains of northern Chile, marking one of the major remaining milestones toward completion of the most elaborate ground-based telescope in history, the Atacama Large Millimeter/submillimeter Array (ALMA).

The ALMA correlator’s 134 million processors will continually combine and compare faint celestial “signals” received by as many as 50 dish-shaped antennas in the main ALMA array, enabling the antennas to work together as a single, enormous astronomical telescope. The correlator can additionally accommodate up to 14 of the 16 antennas in the Atacama Compact Array (ACA), a separate part of ALMA provided by the National Astronomical Observatory of Japan (NAOJ), for a total of 64 antennas. In radio telescope arrays, sensitivity and image quality increase with the number of antennas.

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