Nine Questions about Black Holes

Australian cosmologist Luke Barnes answers nine questions submitted to him by a young student about black holes. If you've ever wondered about any of these questions, or even if you haven't, you'll want to watch the video Barnes has put together on this. Here are the questions:

1. How do scientists know there is a supermassive black hole in the centre of every galaxy?
2. Many sites say scientists don’t know how supermassive black holes are formed. Are there any theories?
3. Why does a star explode into a supernova when it runs out of energy?
4. If it has run out of energy, where does the energy for the explosion come from?
5. Why do extremely dense objects have so much gravity?
6. Does a black hole really ‘blow out’ matter sometimes and why?
7. When a black hole consumes more matter does its gravity increase?
8. Can black holes die?
9. Is it possible for a black hole to have an ‘other side’ and if so what could it be?

And here are Barnes' answers to these questions: