Black Hole Observed by X-Ray Satellite

eldavojohn writes "Scientists at JAXA and NASA used the Japanese Suzaku satellite to collect data and observations at a distance nearer to a black hole than we've ever been. From the article: 'The observations include clocking the speed of a black hole's spin rate and measuring the angle at which matter pours into the void, as well as evidence for a wall of X-ray light pulled back and flattened by gravity. The findings rely on a special feature in the light emitted close to the black hole, called the "broad iron K line," once doubted by some scientists because of poor resolution in earlier observations, now unambiguously revealed as a true measure of a black hole's crushing gravitational force.' Suzaku also has been providing images and data of super novas and their activities. It's always nice to see national space agencies working together, it almost gives me hope that the world might one day be united in space exploration."

Comments

Re:Serious Question

[khayman80]

I have never found a really good explanation for this: How do we know a blackhole truly has an infinite density, and not just so incredibly dense that it, in fact, has a stronger gravity than even light can escape? My mind has a difficult time with something becoming infinitely small. I can understand it becoming so tight that there is no space between the smallest particles, but cannot fathom something smaller than that.

Good question. Short answer: we don't know.

Long answer: According to the General Theory of Relativity, black holes have all their mass contained in a geometric point called the "singularity". This singularity is surrounded by a finite-sized spherical boundary called the "event horizon" which is defined as the locus of points where not even light can escape the gravity of the singularity. Because nothing (that we know of) can travel fast than light, the event horizon is a seemingly impenetrable barrier to any investigation of the singularity itself.

So we're unlikely to view a singularity directly and measure its size. On the other hand, most physicists are convinced that the General Relativistic description of the singularity as a literal geometric point most be wrong. They believe this because very small objects are governed by quantum mechanics, and a new theory (which does not exist yet) called "Quantum Gravity" must take over at densities like those found in singularities.

I'm generally a fairly skeptical chap, and it took a long time to even convince me that event horizons exist. For the longest time, all "proofs" of black holes basically said "here is something that is more dense than a neutron star, and since the ONLY THING more dense than a neutron star is a black hole, this object must be a black hole." I was never really convinced that there weren't other objects denser than neutron stars that didn't actually have event horizons, so this argument never swayed me. These recent observations seem to conclusively prove that event horizons exist, but singularities are an entirely different matter. We'll have to wait for the final word on that subject...