• Question: Since light is the fastest thing known in the universe and cannot escape a black hole does that mean there is a power inside a black hole that is faster than light?

    Asked by jake to Heather, Helen, Hugh, Jane, Julian on 7 Nov 2014.
    • Photo: Julian Onions

      Julian Onions answered on 7 Nov 2014:

      No – there is nothing we know of that can go faster than the speed of light.
      It’s a bit like throwing a ball up into the air. It comes back to you. If you throw it faster, it takes longer to come back. If you throw it really really fast, and this requires a rocket basically, it will never come back. It will have passed the “escape velocity” of the Earth, which is about 7 miles a second.
      If the earth was bigger, you’d have to throw even harder, and the 7 miles a second would go up. Eventually if something is big enough, even going at the speed of light you can’t escape it, and then we have a black hole.

    • Photo: Helen Johnson

      Helen Johnson answered on 10 Nov 2014:

      No, as Julian said there’s nothing that can go faster than the speed of light (about 300 000 km/s). If you are accelerating something (e.g. particles in the LHC), as you approach the speed of light you have to keep putting more and more energy in to increase the speed by just a small amount. Black hole activity is basically ‘powered’ by the extremely strong gravitational field that they have. One of the ways we can ‘see’ black holes is by observing matter falling into them, which releases lots of energy – as light, X rays, radio, even gamma rays!

Comments