Giant Black Hole At Milky Way's Core Stays Slim

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)."

So who cares?

[tetrahedrassface]

So is this story about the black hole, or about the fact that one place got the story right, while another author got confused? Sounds like a hit job to me, and probably better ways to fulfill vendettas.. Just sayin'...

gas expansion means...?

[MadCow42]

>> 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

If there is a dense enough concentration of gas that thermal expansion (i.e. pressure) can keep it out of the gravity well, then is there enough density to actually call that an atmosphere? It's an interesting thought... although going from "atmosphere" to anything else (life, etc.) has about a billion hurdles in-between.

I would assume that in the disc there is a range of concentration/pressure, but never thought it would reach/exceed our atmospheric pressure. That would be cool.

MadCow.