Australia and South Africa today submitted their final bids to host the Square Kilometre Array, which, once built, will be the largest and most sensitive radio telescope in the world.

The array will involve 3,000 15-metre-wide antennas arranged in five spiral arms radiating out up to 3,000 kilometres from the central hub — adding up to one square kilometre of total collecting area. Australia is proposing to build the array in the mostly empty interior of Western Australia, with outstations as far away as New Zealand. South Africa would build the array in the Karoo desert, with parts extending into eight neighbouring countries, including islands in the Indian Ocean (see ‘Giant telescope offered choice of homes’).

Over the next few months a group of external experts will scrutinize the bids, with a decision on the winner expected early next year. Construction of the €1.5 billion (US$2 billion) array is planned to begin in 2016.

Image: Artist’s impression of SKA dishes. Courtesy of SPDO/Swinburne Astronomy Productions.