In 1998 astronomers made an astonishing discovery—the expansion of the Universe is accelerating. The discovery required a complete rethink of the standard model used to explain how the Universe works.
“Now we know that stars, planets, galaxies and all that we can see make up just four per cent of the Universe,” says Dr Tamara Davis, a University of Queensland astrophysicist.
“About 23 per cent is dark matter. The balance is thought to be dark energy, which we know very little about.”