There's a black hole called Sagittarius A* at the centre of our galaxy. It has four million times the mass of the sun, but is only around the size of Mercury's orbit. It's 26,000 light years away, but let's say some unfortunate mishap brought you within a light year or two of that behemoth. What would happen?
Tagged With the galaxy
Count up all the stuff in a galaxy and you should have a pretty good understanding of how much light is being emitted. But that doesn't seem to be the case for our own Milky Way. Our galaxy has a source of extra gamma rays, the highest-energy light, right in its centre. And scientists don't know where all that energy's coming from.