Giant Black Hole At Milky Way's Core Stays Slim 61
thomst writes "A team of researchers from Harvard and MIT announced at the 215th meeting of the American Astronomical Society a new theoretical model of how the super-massive black hole at the center of the Milky Way consumes gas from surrounding star clusters, based on a million seconds of observation by the orbital Chandra X-ray telescope. Astronomers had previously believed that the object, known as Sagittarius A* (pronounced 'Sagittarius A-Star') consumed only around one percent of the gases it stripped from the star clusters around it, but the new model reduces its consumption to 0.01 percent (i.e. — two orders of magnitude). Physorg.com's uncredited reporter gets the story right, while space.com's Andrea Thomspon clearly doesn't understand the mechanism behind the phenomenon (essentially, thermal conduction from the extremely-hot accretion disk heats the surrounding gas, causing it to expand, and thus move away from Sagittarius A*'s gravity well)."
1 million seconds (Score:4, Informative)
Authorship and accuracy (Score:3, Informative)
Actually, the Space.com story does mention the correct mechanism ("It also creates pressure that helps some stellar winds avoid the black hole's gravitational grasp altogether."), but also a second one ("The conduction causes some of the heat in the gas to travel outwards, reducing the strength of the radiation that results from the black hole's consumption.") that sounds a bit odd. Physorg doesn't credit a reporter because they're printing a CfA-authored story (as evidenced by the "Provided by Harvard-Smithsonian Center for Astrophysics").
paper (Score:5, Informative)
Re:Galactic Voids.... (Score:1, Informative)
The idea that there are "white holes" on "the other side" of black holes is pretty much without support.