ASKAP is Australian Square Kilometer Array Pathfinder. It is a radio telescope located in western Australia. The telescope is operated by CSIRO. CSIRO is Commonwealth Scientific and Industrial Research Organisation. The construction of the telescope commenced in 2009 and it became operational in 2012.
There are 36 identical parabolic antennas in the array. Each antenna is 12 metres in diameter. They have a total collecting area of 4,000 square metres. The phased array feed in the antennas increases the field of view.
The ASKAP is located in Murchison district of Australia. The district was chosen as the construction site as it is radio-quiet. This is because the region has low population density.
Data in the telescope
The data obtained from the telescope is transmitted to a super computer. The computer acts as a radio correlator. This supercomputer is located at the Pawsey Supercomputing Centre in Perth, Australia.
The ASKAP mainly focuses on the following studies:
- Evolution and formation of galaxies through high resolution surveys
- Galaxy formation and gas evolution through HI surveys
- Evolution of magnetic fields through polarisation surveys
- Characterization of radio transient sky
The highest priority is given to develop an evolutionary map of the universe. Under this project, the telescope is to detect more than 70 million radio sources. So far 2.5 million radio sources are known to humans. Most of these radio sources are black holes, galaxies.
Astronomers measured intergalactic medium using the observations made with ASKAP. The Intergalactic medium is the physical space between galaxies. Several studies confirm that the galaxies occupy only a tenth of the total space in the universe. The void between them is believed to be filled with rarefied plasma which is organised in a filamentary structure. This raris called intergalactic medium.
Discoveries-Odd Radio Circle
The astronomers discovered odd radio circles (ORC) using ASKAP. The ORCs are highly circular and brighter along their edges. They are not visible at X-ray, visible and infrared wavelengths. But are visible in radio wavelength. Some of the ORCs observed through ASKAP had optical galaxies in the centre. With this, the astronomers believe that the galaxies might have formed these objects.