Astronomy Photo of the Day — MS0735.6+7421

Meet MS0735.6+7421: a galaxy cluster located at a distance of 2.6 billion light-years from Earth, in the constellation of Camelopardalis. Like all clusters, MS0735.6+7421 (we’ll call it MS0735 for short) is a loose collection of galaxies that are held together by the force of gravity.

via Astronomy Photo of the Day — MS0735.6+7421.

Video: How do black holes evaporate?

Nothing lasts forever, not even black holes. According to Stephen Hawking, black holes will evaporate over vast periods of time. But how, exactly, does this happen?

The actor Stephen Hawking is best known for his cameo appearances in Futurama and Star Trek, you might surprised to learn that he’s also a theoretical astrophysicist. Is there anything that guy can’t do?

One of the most fascinating theories he came up with is that black holes, the universe’s swiffer, can actually evaporate over vast periods of time.

Quantum theory suggests there are virtual particles popping in and out of existence all the time. When this happens, a particle and its antiparticle appear, and then they recombine and disappear again.

When this takes place near an event horizon, strange things can happen. Instead of the two particles existing for a moment and then annihilating each other, one particle can fall into the black hole, and the other particle can fly off into space. Over vast periods of time, the theory says that this trickle of escaping particles causes the black hole to evaporate.

via Video: How do black holes evaporate?.