Science news has been a buzz about a whole posse of new black holes discovered in the constellation of Andromeda. The reason for this is not that these have suddenly been discovered, but rather that a new paper on results from Chandra is being published in the Astrophysical Journal last year, and the press releases have been published.
Animal Magnetism
One of the challenges to understanding black holes is that when things get close to a black hole, things get complicated. We actually have a good description of black holes by themselves, but the description of the heated material near a black hole is complex. To understand the behavior of this material you need to account for not only the gravitational attraction of the black hole, but also things such as magnetic fields. To model active black holes, you need sophisticated computer simulations, and those simulations rely on certain assumptions about how black holes interact.
No Doughnut
Within most galaxies is a supermassive black hole. These black holes can have a mass of millions or even billions of Suns. When actively consuming material, these black holes can produce tremendous amounts of energy, and can be seen as quasars, blazars and radio galaxies, depending upon the way they are oriented relative to our vantage point. At least that’s been our understanding. But now a new paper in the Astrophysical Journal has thrown a wrench in one part of that idea.
The Inbetweeners
Yesterday I mentioned the possibility that a mid-sized black hole might explain why the Trapezium cluster is gravitationally bound. If such an black hole were discovered it would be a really big deal.
Non-Singular Black Holes
The basic model of a black hole can be summed up as follows: gravity wins. The root cause of all black holes—be they tiny primordial black holes, solar mass black holes, or supermassive galactic black holes—is gravity. Squeeze enough mass into a small enough volume and gravity does the rest.
Heart of Darkness
Star formation within a galaxy is a complex process. We have models of galaxy formation, but one of the difficulties with these models has been that they predict a greater formation of stars in large galaxies than we observe. This would seem to indicate that there is some mechanism that hinders star formation within large galaxies. Basically at some point in the galaxy’s formation there must be something that pushes gas out of the galaxy, preventing it from forming into stellar nurseries.
Hidden Giants
When WISE completed its full sky survey, about 1.6 million “hidden” black holes were discovered. Some of these are billions of light years away, which will help give us a better understanding of how these supermassive black holes evolve within galaxies.
Consume Mass Quantities
A recent Cosmos episode not withstanding, there is no reason to suspect that entering a black hole would take you to an alternate universe. If you were to fall into a black hole, you would simply be in the black hole. What happens to you after that depends upon the nature of quantum gravity, which we still don’t fully understand.
Why Hawking is Wrong About Black Holes
The recent controversy over black holes has put Stephen Hawking in the spotlight. It turns out what he proposes isn’t that controversial, and isn’t necessary to resolve the dreaded firewall paradox.