Deskarati predicts the SKA will be the most important cosmological construction in our life time. We are so excited about this wondrous telescope and just can’t wait for it to get under way. What with SKA and LHC both likely to produce mind blowing results in the next twenty years, we truly do live in exciting times – Deskarati –
The Square Kilometre Array (SKA) is a radio telescope in development which will have a total collecting area of approximately one square kilometre. It will operate over a wide range of frequencies and its size will make it 50 times more sensitive than any other radio instrument. It will require very high performance central computing engines and long-haul links with a capacity greater than the current global Internet traffic. It will be able to survey the sky more than ten thousand times faster than ever before. With receiving stations extending out to distance of 3,000 km from a concentrated central core, it will continue radio astronomy’s tradition of providing the highest resolution images in all astronomy. The SKA will be built in the southern hemisphere, either in South Africa or Australia, where the view of our own galaxy, the Milky Way, is best and radio interference least. With a budget of €1.5 billion, construction of the SKA is scheduled to begin in 2016 for initial observations by 2019 and full operation by 2024.
The SKA is a global collaboration of 20 countries which may provide answers to fundamental questions about origin and evolution of the Universe.
The SKA will be a highly flexible instrument designed to address a wide range of questions in astrophysics, fundamental physics, cosmology and particle astrophysics. It will be able to probe previously unexplored parts of the distant Universe.
Extreme tests of general relativity
For almost ninety years, Einstein’s theory of general relativity has precisely predicted the outcome of every experiment made to test it. Most of these tests, including the most stringent ones, have been carried out using radio astronomical measurements. By using pulsars as cosmic gravitational wave detectors, or timing pulsars found orbiting black holes, astronomers will be able to examine the limits of general relativity such as the behaviour of space and time in regions of extremely curved space. It will then be revealed whether Einstein was correct in his description of space, time and gravity, or if new physics is needed.
Galaxies, cosmology, dark matter and dark energy
The sensitivity of the SKA in the 21-cm hydrogen line will map a billion galaxies out to the edge of the Universe. The large-scale structure revealed will determine the processes by which galaxies formed and grew. Imaging hydrogen through the Universe will provide a three-dimensional picture of the first ripples of structure which will then form individual galaxies and clusters. This will probe the effects of the mysterious “dark energy” that is pushing the Universe apart.
Probing the dark ages—the first black holes and stars
The SKA will be able to fill in the gap—the so called dark ages—between 300,000 years after the Big Bang when the Universe became transparent, and a billion years later when young galaxies are seen. By observing the primordial distribution of gas, the SKA will see how the Universe gradually lit up as its stars and galaxies formed and then evolved.
The origin and evolution of cosmic magnetism
It is still not possible to answer basic questions about the origin and evolution of cosmic magnetic fields, but it is clear that they are an important component of interstellar and intergalactic space. By mapping the effects of magnetism on the radiation from very distant galaxies, the SKA will reveal the form of cosmic magnetism and the role it has played in the evolving Universe.
The cradle of life
The SKA will be able to detect extremely weak extraterrestrial signals, and may even spot other planets capable of supporting life. Astrobiologists will use the SKA to search for amino acids, the building blocks of life, by identifying spectral lines at specific frequencies.