July 7, 2015

The galaxy was uncovered in radio emission travelling to Earth using CSIRO’s Australian SKA Pathfinder telescope (ASKAP), located at the Murchison Radio-astronomy Observatory (MRO) in Western Australia.
ASKAP is one of three precursor telescopes to the Square Kilometre Array, which will be the world’s largest radio telescope when built.
The five-billion-year-old radio emission was stamped with the ‘imprint’ of hydrogen gas it had travelled through on its way to Earth. The gas absorbs some of the emission, creating a tiny dip in the signal. “At many observatories, this dip would have been hidden by background radio noise, but our site is so radio quiet it stood out clearly,” Dr James Allison said.
The MRO is located in a remote part of Western Australia, and was chosen as one of two ideal radio-quiet sites to develop the Square Kilometre Array (SKA), the other being located in South Africa.
The Australian site will host the low frequency component of SKA, composed initially of around 130,000 low frequency antennas spread over 65 kilometres.

Images
(Left) The Australian SKA Pathfinder radio telescope in Western Australia.
(Right) Close-up of SKA1 LOW, the SKA’s low frequency aperture arrays and ASKAP dishes in Australia.