A super telescope has begun the most detailed survey of the Universe ever undertaken.
The aim of the five-year programme is to shed light on Dark Energy – the mysterious force thought to drive an accelerated expansion of the Universe.
The instrument effectively contains 5,000 mini-telescopes. Each one can image a galaxy every 20 minutes.
In just one year scientists will have surveyed more galaxies than all the other telescopes in the world combined.
What is Dark Energy?
The Big Bang theory of the creation of the Universe originally predicted that its expansion would slow down, and that it would possibly begin to contract as a result of the pull of gravity.
However, in 1998, astronomers were shocked to discover that not only was the Universe continuing to expand, but that this expansion was also accelerating.
The most widely held view is that something is counteracting the pull of gravity – and that something has been termed Dark Energy.
It has been calculated that Dark Energy makes up most of the Universe. Indeed, the atoms that build planets, stars and galaxies probably account for just 5%.
“It is just embarrassing to live in a Universe where you only know 5% of it,” he told BBC News.
“The nature of Dark Energy, and what it is, may well lead to a revolution in physics – the whole of physics!”