Australian Square Kilometre Array Pathfinder


The Australian Square Kilometre Array Pathfinder is a radio telescope array located at Murchison Radio-astronomy Observatory in the Australian Mid West. It is operated by the Commonwealth Scientific and Industrial Research Organisation and forms part of the Australia Telescope National Facility. Construction commenced in late 2009 and first light was in October 2012.
ASKAP consists of 36 identical parabolic antennas, each 12 metres in diameter, working together as a single astronomical interferometer with a total collecting area of approximately 4,000 square metres. Each antenna is equipped with a phased-array feed, increasing the field of view. This design provides both fast survey speed and high sensitivity.
The facility began as a technology demonstrator for the international Square Kilometre Array, a planned radio telescope which will be larger and more sensitive. The ASKAP site has been selected as one of the SKA's two central locations.

Description

Development and construction of ASKAP was led by CSIRO Astronomy and Space Science, in collaboration with scientists and engineers in The Netherlands, Canada and the US, as well as colleagues from Australian universities and industry partners in China.

Design

The construction and assembly of the dishes was completed in June 2012.
ASKAP was designed as a telescope with a wide field-of-view, large spectral bandwidth, fast survey speed, and a large number of simultaneous baselines.
Feed receiver on an ASKAP antenna. This feed includes 188 individual receivers, to greatly extend the Field of View of an ASKAP 12m dish to 30 square degrees.
ASKAP is located in the Murchison district in Western Australia, a region that is extremely "radio-quiet" due to the low population density and resulting lack of radio interference that would otherwise interfere with weak astronomical signals. The radio quiet location is recognised as a natural resource and protected by the Australian Commonwealth and Western Australia State Government through a range of regulatory measures.
Data from ASKAP are transmitted from the MRO to a supercomputer at the Pawsey Supercomputing Centre in Perth. The data are processed in near-real-time by a pipeline processor running purpose-built software. All data are made publicly available after quality checks by the ten ASKAP Survey Science Teams.

Science

During ASKAP's first five years of operation, 75% of its observing time was used for large Survey Science Projects. ASKAP was intended to study the following topics:
  1. Galaxy formation and gas evolution in the nearby Universe through extragalactic HI surveys
  2. Evolution, formation and population of galaxies across cosmic time via high resolution, continuum surveys
  3. Characterisation of the radio transient sky through detection and monitoring of transient and variable sources, and
  4. Evolution of magnetic fields in galaxies over cosmic time through polarisation surveys.

    Initial surveys

Ten ASKAP Survey Science Projects were selected to run in the first five years of operations. They were:

Highest Priority

In May 2020, astronomers announced a measurement of the intergalactic medium using six fast radio bursts observed with ASKAP; their results confirm existing measurements of the missing baryon problem.
Odd radio circles are a possible "new class of astronomical object" discovered at ASKAP.