10 Biggest Unexplained Mysteries Of The Universe

3. The Singularity

Black holes are arguably the most intriguing objects in the entire universe and have been a subject of fascination for scientists and science-fiction writers for the last 100 years.

Black holes consist of two main features: the event horizon, the bit you can see (or rather can't see), which is the point at which light can no longer escape the pull of its gravity leaving behind nothing but a black circle; and the singularity, the inside of the black hole, the stuff that lies beyond the event horizon.

The difficulty with black holes is quite simple: you need light to see. When you have something that sucks in all of the available light, it makes it pretty hard to see what's going on inside. As such, no-one has any idea what is happening on the inside of a black hole.

Thanks to the late Professor Stephen Hawking, we understand that black holes radiate energy and therefore slowly lose their size over extremely long periods of time, so whatever is going on in there is using up its fuel.

One such prediction for what happens in the singularity is the idea that information breaks down on an atomic level, i.e. the rules of physics don't apply anymore. This could mean that, if you somehow were able to survive getting inside, you wouldn't be able to tell the difference between a planet and a banana.