Jan 7, 2009 | 10
LONG BEACH, CALIF.—One of the oddities of the universe revealed over the past decade is that galaxies and the giant black holes at their hubs fit together as if they were made for each other. This is one of those facts of life that sound obvious at first glance, but get stranger the more you think about them.
A giant black hole is a formidable beast, surely able to bend the surrounding swarm of stars to its will. Yet even a giant black hole is still fairly small by the standards of a galaxy, so the galaxy should pay little heed to the monster within. The monster, for its part, is in direct contact with only a fairly small neighborhood and should be oblivious to what happens in the galaxy at large.
Yet astronomers find that black holes consistently have about 0.1 percent of the mass of their galaxies—or, more precisely, of the portion of their galaxies that has an spheroidal shape (which, for an spheroidal galaxy, is the whole thing and, for a spiral galaxy such as our Milky Way, is only the innermost parts). Some astronomers argue that the black hole mass is related not to the mass of the galaxy per se, but to the velocity of the stars, but it amounts to much the same thing: black holes and their host galaxies are blood brothers.
Jan 6, 2009 | 1
The center of the Milky Way galaxy is a forbidding place, dominated by what astronomers strongly suspect is a black hole four million times the mass of the sun. But a new study provides evidence that stars are able to form there, despite the violent conditions stirred up by the supermassive gobbler.
The findings indicate that the clouds of gas at the galaxy's core must be denser than previously believed to coalesce into stars while resisting being ripped apart by the black hole's gravitational pull. Study leader Elizabeth Humphreys, an astronomer at the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass., presented the results yesterday at the semiannual meeting of the American Astronomical Society in Long Beach, Calif.
Sep 30, 2008 | 15
A federal judge has tossed out a case challenging the operation of the world's biggest particle accelerator—not that the Large Hadron Collider (LHC) is running, anyway.
Judge Helen Gillmor of the U.S. District Court in Hawaii dismissed the lawsuit Friday, saying the American judicial system has no jurisdiction over the $8-billion LHC, which is housed in a circular tunnel straddling the Swiss-French border. The New York Times is reporting on the dismissal today.
The suit was filed by a retired radiation safety officer, Walter Wagner, and Spanish science writer Luis Sancho, MSNBC's Cosmic Log has previously noted. The two claimed that the operator of the LHC, the European Organization for Nuclear Research (CERN), and its backers failed to show that smashing protons at nearly the speed of light wouldn't produce mini black holes that could obliterate Earth.
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