Friday FACTS: Black holes

Happy Friday!

I'm at Anders (not my Anders, but my good friend) and Charlotte's fantastic cabin at Nordseter (Sjusjøen). We just had a nice dinner, we're drinking wine, talking, and there's a fire in the fireplace <3 I'm about to put away my laptop for the weekend, but before I do that, what could fit better now than ten facts about black holes? Close to nothing :D Here goes:

1. Black holes are called “black” because they swallow all light, and no light (or anything) can ever escape it
2. Black holes are made when stars die and collapse (*sad*)
3. Black holes are super super super dense, and NOTHING have a higher density than a black hole
4. It's not really like what people think of as a hole, but maybe more like what we would normally think of as a sphere. But then again, it has the "traplike" properties of a hole (since you can fall into is, as if it was a hole in the ground), so you can probably think about it as a three dimensional hole ;)
5. A black hole with the size of a sugar cube weighs the same as the entire earth: 1000000000000000000000000kg (24 zeros!) - 1 septillion kilos :D
6. We know nothing about what happens inside black holes
7. If a black hole came into our solar system it would swallow the earth. This is extremely unlikely, but it’s still more likely than for example winning the lottery ten times in a row (but less likely than being struck by lightening)
8. Black holes have a horizon (or really an "event horizon", which is the boarder of the black hole) where time stands still (at least it looks like it’s standing still if we are looking at a person who is falling into it) this horizon is the point of no return, where it's absolutely impossible to escape falling into the hole. It's really just like as a a clock runs a bit slower closer to sea level than up on a space station, a clock run really slow near black holes, and this all have to do with gravity 
9. If you fall into a black hole you would be stretched (to death) like spaghetti, since whatever part of your body that reaches the horizon first will feel soooo much more gravity (since the hole is so dense and heavy) than the rest of the body that's outside the horizon
10. When black holes collide, they make gravitational waves - which were discovered last Thursday!

By the way: today I managed to finally make this figure I was talking about yesterday, so then I'm one step closer to a new article. Next week I want to finish the rest of the figures to the article, and then I'm suddenly quite close to finishing the thing.

PS. This week I just have to give you a sort of fact number 11: we don't believe that inside black holes you find book shelves. (Hint: "Interstellar")