Origins of the universe

The SKA will enable scientists to look back in time to the origin of the universe.

Already, our telescopes have probed back to a period when the universe was about one-tenth of its current age when stars, planets and galaxies were already formed. Now the SKA will help us understand how they were formed by probing a time when the universe consisted of only a dark void of hydrogen gas.

To capture this moment, the SKA telescope will pick up the weak signals coming from hydrogen gas emitted at a time when the universe was in the first one per cent of its life. It will have a collecting area of around one million square metres, about 50 times larger than anything that exists today.

The radio signals will reach the Earth in the FM part of the radio spectrum which is saturated with man-made signals over most of the Earth's inhabited regions. Australia's bid will stress that WA's Midwest is the most "radio quiet" region on Earth, yet it's still accessible to astronomers and engineers from around the world.

The vast extent of the Australia continent also allows for the positioning of dishes over the thousands of kilometres needed to discovery the sources of the first light.

Key projects

The Square Kilometre Array will be a highly flexible instrument designed to address a wide range of fundamental questions in astrophysics, fundamental physics, cosmology, particle astrophysics and astrobiology.

It will be able to probe previously unexplored parts of the universe.

From this wealth of possible science, a number of key science projects addressing physics beyond our current understanding have been selected:

• Evolution of galaxies, cosmology, dark matter and energy
• The Cradle of Life - searching for life and planets
• Extreme tests of general relativity with pulsars and black holes
• Probing the Dark Ages - the first black holes and stars
• The origin and evolution of cosmic magnetism
• Exploration of the unknown.

While these projects address important scientific questions of our time, we cannot foresee the unexpected discoveries that the SKA will make. What is clear is that the SKA will transform our understanding of the Universe and its fundamental physics and complexity.