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Wednesday, May 10, 2006 |
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Wednesday, May 10
Thursday, May 11 Click here for links to descriptions of each event. |
 Chance of Showers 71º/51º
Extended Forecast |
Secon Level 3 |
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Wednesday, May 10 -Italian Wedding w/Meatballs -Texas Style Meatloaf Sandwich -Diner Style Patty Melt -Chicken a la Mer -Stuffed Cabbage -Greek Chicken Panini with Feta Cheese -Siclian Style Pizza The Wilson Hall Cafe accepts Visa, Master Card, Discover and American Express. |
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Wednesday, May 10
Thursday, May 11
Chez Leon Menu |
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When it comes to charting the explosive, spectacular deaths of massive stars, the Sloan Digital Sky Survey has something most telescopes don't. Although its mirror is a moderately sized 2.5 meters across, a large digital camera allows it to take broad swaths of data at once, making it ideally suited to track supernovae. "The Sloan Survey is by far the most ambitious survey of the sky that has ever been undertaken," said Joshua Frieman, theoretical astrophysicist at Fermilab. From New Mexico, the SDSS sends its data to Fermilab for processing before it is analyzed by collaborators all over the world.
One kind of supernova occurs when a white dwarf--a star that has burned up all its hydrogen--begins sucking in mass from a companion star. At some point, the white dwarf becomes unstable and explodes with the brilliance of a hundred billion ordinary stars. "It takes a few weeks for the supernova to get as bright as it is going to get, and a few months for it to fade," said Gajus Miknaitis, a postdoc in Fermilab's Experimental Astrophysics Group. To find and measure supernovae, astronomers take repeated images of the same patch of sky, comparing how the brightness of their target objects changes with time.
All supernovae that come from white dwarfs have roughly the same peak brightness, making them useful for solving one of the biggest mysteries in physics today: that of dark energy. "It's a name for whatever is causing the expansion of the universe to speed up," says Fermilab's John Marriner, a collaborator on the project. If the universe began with a big bang--as the evidence strongly suggests--gravity should slow its acceleration with time. But now evidence indicates the universe has stopped slowing down and is speeding up. "That doesn't happen if the universe is filled with normal matter," Frieman says. To understand dark energy better, astronomers use the standard peak brightness of supernovae to tell how far away objects are in the sky, measuring precisely how fast the universe has been expanding in different periods of cosmic history.
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Space.com,
May 8, 2006:
Recycled Universe: Theory Could Solve Cosmic Mystery One of the biggest mysteries in cosmology could be explained by a controversial theory in which the universe explodes into existence not just once, but repeatedly in endless cycles of death and rebirth. Called the cyclic universe theory, it could potentially explain why a mysterious repulsive form of energy known as the "cosmological constant" and which is accelerating the expansion of the universe is several orders of magnitude smaller than predicted by the standard Big Bang model. In a new study detailed in the May 5 issue of the journal Science, Paul Steinhardt of Princeton University and Neil Turok of Cambridge University propose that the constant was once much larger, but that its value decayed with each incarnation of the universe. The cosmological constant, also known as "lambda", is thought to be a form of energy that gravitationally repels itself and causes the expansion of the universe to speed up.
Einstein initially proposed it as a counterforce to the gravitational attraction of matter to explain why the universe appeared static, neither growing nor shrinking. He later discarded the idea, however, when observations by astronomer Edwin Hubble revealed the universe was in fact expanding.
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| New report gives context for the study of very small things | ||
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| At yesterday's R&D Caucus on Capitol Hill, the High Energy Physics Advisory Panel launched a brand-new report. Titled, Discovering the Quantum Universe, the report explains how researchers seek to understand the universe by studying the "microscopic and subatomic" world of quantum physics. In simple language, it describes the meaning of the Higgs boson, the quest to understand dark matter, extra dimensions and the inexplicable lack of antimatter in the universe, and it describes possible ways to realize Einstein's dream of finding an ultimate, unified force to explain all of nature.
The report asserts that these seemingly insurmountable concepts might be tackled using particle accelerators. "Starting with the discovery of the electron, particle physicists have ventured successively deeper into the unseen world within the atom," it states. "They have discovered a structure and simplicity neither expected nor predicted, even by Einstein."
You can find Discovering The Quantum Universe online here. A full report from the R&D Caucus, which included a lecture by best-selling author Brian Greene, will appear in Friday's issue of ILC NewsLine.
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Striping D Road
Batavia Road entrance closed to cars and bicycles
Main Ring Road, near A0, closed Monday-Friday
Fundraiser for John LaFleur: Dunk tank volunteers needed!
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