It will launch in 2019 and map the spread of galaxies and clusters of galaxies over 10 billion years of cosmic history.

BBC: Dark discussion ahead for Europe and US

So do measurements of how the largest-scale structures in the universe formed over time and of how clusters of galaxies are held together.

ECONOMIST: Cosmology

In the near Universe, for example, it should fit with the detailed information we now have on the way clusters of galaxies are dotted across the sky.

BBC: Science & Environment

It will allow astronomers to peer back into the universe's Dark Ages, a period roughly 400, 000 to 800m years after the Big Bang, during which things cooled enough to allow the first large-scale objects, such as galaxies and clusters of galaxies, to form.

ECONOMIST: The Square Kilometre Array

Scientists had thought that medium black holes might lie hidden among millions of stars in globular clusters, which sit within galaxies containing hundreds of billions of stars.

MSN: Existence of middleweight black holes nearly ruled out