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New Radio Telescope Could Save World Billions

December 2, 2012 Leave a comment

A small pocket of Western Australia’s remote outback is set to become the eye on the sky and could potentially save the world billions of dollars. The Murchison Widefield Array (MWA) radio telescope, unveiled today, Friday 30 November, will give the world a dramatically improved view of the Sun and provide early warning to prevent damage to communication satellites, electric power grids and GPS navigation systems.

The $51 million low-frequency radio telescope will be able to detect and monitor massive solar storms, such as the one that cut power to six million people in Canada in 1989 during the last peak in solar activity. In 2011, experts warned that a major solar storm could result in damage to integral power supplies and communication networks of up to US$2 trillion – the equivalent of a global Hurricane Katrina.

The MWA will aim to identify the trajectory of solar storms, quadrupling the warning period currently provided by near-Earth satellites. This is timely as the Sun is due to re-enter peak activity in 2013, with a dramatic increase in the number and severity of solar storms expected, with the potential to disrupt global communications and ground commercial airlines.

Full Story: http://www.icrar.org/news/news_items/new-radio-telescope-could-save-world-billions

MESSENGER Finds New Evidence For Water Ice At Mercury’s Poles

December 2, 2012 Leave a comment

Permanently Shadowed Polar Craters. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington/National Astronomy and Ionosphere Center, Arecibo Observatory

Permanently Shadowed Polar Craters. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington/National Astronomy and Ionosphere Center, Arecibo Observatory

New observations by the MESSENGER spacecraft provide compelling support for the long-held hypothesis that Mercury harbors abundant water ice and other frozen volatile materials in its permanently shadowed polar craters.

Three independent lines of evidence support this conclusion: the first measurements of excess hydrogen at Mercury’s north pole with MESSENGER’s Neutron Spectrometer, the first measurements of the reflectance of Mercury’s polar deposits at near-infrared wavelengths with the Mercury Laser Altimeter (MLA), and the first detailed models of the surface and near-surface temperatures of Mercury’s north polar regions that utilize the actual topography of Mercury’s surface measured by the MLA. These findings are presented in three papers published online today in Science Express.

Given its proximity to the Sun, Mercury would seem to be an unlikely place to find ice. But the tilt of Mercury’s rotational axis is almost zero — less than one degree — so there are pockets at the planet’s poles that never see sunlight. Scientists suggested decades ago that there might be water ice and other frozen volatiles trapped at Mercury’s poles.

Full Story: http://www.nasa.gov/mission_pages/messenger/media/PressConf20121129.html

Image Release: A Radio-Optical View Of The Galaxy Hercules A

December 2, 2012 Leave a comment

Credit: NASA, ESA, S. Baum and C. O'Dea (RIT), R. Perley and W. Cotton (NRAO/AUI/NSF), and the Hubble Heritage Team (STScI/AURA)

Credit: NASA, ESA, S. Baum and C. O’Dea (RIT), R. Perley and W. Cotton (NRAO/AUI/NSF), and the Hubble Heritage Team (STScI/AURA)

Spectacular jets powered by the gravitational energy of a supermassive black hole in the core of the elliptical galaxy Hercules A illustrate the combined imaging power of two of astronomy’s cutting-edge tools, the Hubble Space Telescope’s Wide Field Camera 3, and the recently upgraded Karl G. Jansky Very Large Array (VLA) radio telescope in west-central New Mexico.

The VLA radio data reveal enormous, optically invisible jets that, at one-and-a-half million light-years long, dwarf the visible galaxy from which they emerge. The jets are very-high-energy plasma beams, subatomic particles and magnetic fields shot at nearly the speed of light from the vicinity of the black hole. The outer portions of both jets show unusual ring-like structures suggesting a history of multiple outbursts from the supermassive black hole at the center of the galaxy.

Full Story: http://www.nrao.edu/pr/2012/herca/
Also: http://hubblesite.org/newscenter/archive/releases/2012/47/image/a/

Even Brown Dwarfs May Grow Rocky Planets: ALMA Sizes Up Grains Of Cosmic Dust Around Failed Star

December 2, 2012 Leave a comment

Astronomers using the Atacama Large Millimeter/submillimeter Array (ALMA) have for the first time found that the outer region of a dusty disc encircling a brown dwarf contains millimetre-sized solid grains like those found in denser discs around newborn stars. The surprising finding challenges theories of how rocky, Earth-scale planets form, and suggests that rocky planets may be even more common in the Universe than expected.

Rocky planets are thought to form through the random collision and sticking together of what are initially microscopic particles in the disc of material around a star. These tiny grains, known as cosmic dust, are similar to very fine soot or sand. However, in the outer regions around a brown dwarf — a star-like object, but one too small to shine brightly like a star — astronomers expected that grains could not grow because the discs were too sparse, and particles would be moving too fast to stick together after colliding. Also, prevailing theories say that any grains that manage to form should move quickly towards the central brown dwarf, disappearing from the outer parts of the disc where they could be detected.

“We were completely surprised to find millimetre-sized grains in this thin little disc,” said Luca Ricci of the California Institute of Technology, USA, who led a team of astronomers based in the United States, Europe and Chile. “Solid grains of that size shouldn’t be able to form in the cold outer regions of a disc around a brown dwarf, but it appears that they do.”

Full Story: http://www.eso.org/public/news/eso1248/

The Beginning Of Everything: A New Paradigm Shift For The Infant Universe

December 2, 2012 Leave a comment

A new paradigm for understanding the earliest eras in the history of the universe has been developed by scientists at Penn State University. Using techniques from an area of modern physics called loop quantum cosmology, developed at Penn State, the scientists now have extended analyses that include quantum physics farther back in time than ever before — all the way to the beginning. The new paradigm of loop quantum origins shows, for the first time, that the large-scale structures we now see in the universe evolved from fundamental fluctuations in the essential quantum nature of “space-time,” which existed even at the very beginning of the universe over 14 billion years ago. The achievement also provides new opportunities for testing competing theories of modern cosmology against breakthrough observations expected from next-generation telescopes. The research will be published on 11 December 2012 as an “Editor’s Suggestion” paper in the scientific journal Physical Review Letters.

The new paradigm provides a conceptual and mathematical framework for describing the exotic “quantum-mechanical geometry of space-time” in the very early universe. The paradigm shows that, during this early era, the universe was compressed to such unimaginable densities that its behavior was ruled not by the classical physics of Einstein’s general theory of relativity, but by an even more fundamental theory that also incorporates the strange dynamics of quantum mechanics. The density of matter was huge then — 1094 grams per cubic centimeter, as compared with the density of an atomic nucleus today, which is only 1014 grams.

Full Story: http://science.psu.edu/news-and-events/2012-news/Ashtekar11-2012