Australian Square Kilometre Array Pathfinder
Encyclopedia
The Australian Square Kilometre Array Pathfinder, or ASKAP, is CSIRO’s new radio telescope
currently under construction at the Murchison Radio-astronomy Observatory (MRO) in Mid West
region of Western Australia
. Construction on ASKAP began in late 2009 and is expected to be completed by 2013.
ASKAP’s combination of fast survey speed and high sensitivity will allow astronomers to answer some fundamental questions about the creation and early evolution of our Universe, and to test theories of cosmic magnetism and predictions from Einstein's theory of general relativity.
ASKAP will also be an important technology demonstrator for the international Square Kilometre Array
(SKA) project, a future international radio telescope that will be the world’s largest and most sensitive. ASKAP's home, the MRO, is also the candidate 'core' site in Australia
and New Zealand
's bid for the SKA.
Once built, ASKAP will form part of CSIRO's Australia Telescope National Facility
along with existing telescopes at Parkes
, Narrabri
and Mopra
.
, each 12 metres in diameter, working together as a single instrument to achieve a total collecting area
of approximately 4,000 square metres.
The unique features that will ASKAP an unprecedented synoptic telescope include a wide field-of-view, large spectral bandwidth, extremely fast survey speed, and excellent u-v coverage.
ASKAP will be located in the Murchison district in Western Australia, a region that is extremely "radio-quiet" due to the low population density and resultant lack of radio interference (generated by human activity) that would otherwise interfere with weak astronomical signals.
The unique radio quiet nature is being recognised as a natural resource and is being protected by the Australian Commonwealth and Western Australia State Government
through a range of protective regulatory measures.
Data from ASKAP will be transmitted from the MRO to a supercomputer
at the Pawsey Supercomputing Centre in Perth
. The data will be converted to images of the sky in near-real-time by a pipeline processor
running the purpose-built ASKAPsoft package. All data will be placed in the public domain after being checked for quality by the ten ASKAP Survey Science Teams.
The ten ASKAP Survey Science Projects are:
Radio telescope
A radio telescope is a form of directional radio antenna used in radio astronomy. The same types of antennas are also used in tracking and collecting data from satellites and space probes...
currently under construction at the Murchison Radio-astronomy Observatory (MRO) in Mid West
Mid West region of Western Australia
The Mid West region is one of the nine regions of Western Australia. It is a very sparsely populated region located on the west coast of Western Australia, extending about north and south of its administrative centre of Geraldton. To the east it extends more than inland to Wiluna in the Gibson...
region of Western Australia
Western Australia
Western Australia is a state of Australia, occupying the entire western third of the Australian continent. It is bounded by the Indian Ocean to the north and west, the Great Australian Bight and Indian Ocean to the south, the Northern Territory to the north-east and South Australia to the south-east...
. Construction on ASKAP began in late 2009 and is expected to be completed by 2013.
ASKAP’s combination of fast survey speed and high sensitivity will allow astronomers to answer some fundamental questions about the creation and early evolution of our Universe, and to test theories of cosmic magnetism and predictions from Einstein's theory of general relativity.
ASKAP will also be an important technology demonstrator for the international Square Kilometre Array
Square Kilometre Array
The Square Kilometre Array 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...
(SKA) project, a future international radio telescope that will be the world’s largest and most sensitive. ASKAP's home, the MRO, is also the candidate 'core' site in Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
and New Zealand
New Zealand
New Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses and numerous smaller islands. The country is situated some east of Australia across the Tasman Sea, and roughly south of the Pacific island nations of New Caledonia, Fiji, and Tonga...
's bid for the SKA.
Description
Development and construction of ASKAP is being led by CSIRO Astronomy and Space Science (CASS), in collaboration with scientists and engineers in The Netherlands, Canada and the USA, as well as colleagues from Australian universities and industry partners in China.Once built, ASKAP will form part of CSIRO's Australia Telescope National Facility
Australia Telescope National Facility
The Commonwealth Scientific and Industrial Research Organisation 's radio astronomy observatories are collectively known as the Australia Telescope National Facility , with the facility supporting Australia's research in radio astronomy....
along with existing telescopes at Parkes
Parkes Observatory
The Parkes Observatory is a radio telescope observatory, 20 kilometres north of the town of Parkes, New South Wales, Australia. It was one of several radio antennas used to receive live, televised images of the Apollo 11 moon landing on 20 July 1969....
, Narrabri
Australia Telescope Compact Array
The Australia Telescope Compact Array is a radio telescope at the Paul Wild Observatory, twenty five kilometres west of the town of Narrabri in Australia....
and Mopra
Mopra Observatory
The 22-metre Mopra Radio Telescope, located near Coonabarabran, New South Wales, is part of the Australia Telescope National Facility, operated by CSIRO. The name hails from the location of the facility close to Mopra Rock a geological formation overlooking the telescope...
.
Design
ASKAP will be made up of 36 identical antennasAntenna (radio)
An antenna is an electrical device which converts electric currents into radio waves, and vice versa. It is usually used with a radio transmitter or radio receiver...
, each 12 metres in diameter, working together as a single instrument to achieve a total collecting area
Antenna effective area
In telecommunications, antenna effective area or effective aperture expresses an antenna's ability to collect an incident radio wave and deliver it as an electrical current at the antenna's terminals...
of approximately 4,000 square metres.
The unique features that will ASKAP an unprecedented synoptic telescope include a wide field-of-view, large spectral bandwidth, extremely fast survey speed, and excellent u-v coverage.
ASKAP will be located in the Murchison district in Western Australia, a region that is extremely "radio-quiet" due to the low population density and resultant lack of radio interference (generated by human activity) that would otherwise interfere with weak astronomical signals.
The unique radio quiet nature is being recognised as a natural resource and is being protected by the Australian Commonwealth and Western Australia State Government
Government of Western Australia
The formation of the Government of Western Australia is prescribed in its Constitution, which dates from 1890, although it has been amended many times since then...
through a range of protective regulatory measures.
Data from ASKAP will be transmitted from the MRO to a supercomputer
Supercomputer
A supercomputer is a computer at the frontline of current processing capacity, particularly speed of calculation.Supercomputers are used for highly calculation-intensive tasks such as problems including quantum physics, weather forecasting, climate research, molecular modeling A supercomputer is a...
at the Pawsey Supercomputing Centre in Perth
Perth, Western Australia
Perth is the capital and largest city of the Australian state of Western Australia and the fourth most populous city in Australia. The Perth metropolitan area has an estimated population of almost 1,700,000....
. The data will be converted to images of the sky in near-real-time by a pipeline processor
Instruction pipeline
An instruction pipeline is a technique used in the design of computers and other digital electronic devices to increase their instruction throughput ....
running the purpose-built ASKAPsoft package. All data will be placed in the public domain after being checked for quality by the ten ASKAP Survey Science Teams.
Science
During ASKAP’s first five years of operation, at least 75% of its time will be used for large Survey Science Projects. ASKAP is expected to make substantial advances in key areas, including the following:- Galaxy formationGalaxy formation and evolutionThe study of galaxy formation and evolution is concerned with the processes that formed a heterogeneous universe from a homogeneous beginning, the formation of the first galaxies, the way galaxies change over time, and the processes that have generated the variety of structures observed in nearby...
and gas evolution in the nearby Universe through extragalactic HIH I regionAn H I region is an interstellar cloud composed of neutral atomic hydrogen , in addition to the local abundance of helium and other elements. These regions are non-luminous, save for emission of the 21-cm region spectral line. This line has a very low transition probability, so requires large...
surveys - Evolution, formation and population of galaxies across cosmic timeCosmic timeCosmic time is the time coordinate commonly used in the Big Bang models of physical cosmology. It is defined for homogeneous, expanding universes as follows: Choose a time coordinate so that the universe has the same density everywhere at each moment in time Cosmic time (also known as time since...
via high resolution, continuum surveys - Characterisation of the radio transient sky through detection and monitoring (including VLBI) of transientTransient astronomical eventA transient astronomical event, often simply called in context by astronomers a transient, is an astronomical object or phenomenon which can be observed for a short period of time...
and variableVariable starA star is classified as variable if its apparent magnitude as seen from Earth changes over time, whether the changes are due to variations in the star's actual luminosity, or to variations in the amount of the star's light that is blocked from reaching Earth...
sources, and - Evolution of magnetic fields in galaxies over cosmic time through polarisation surveys.
ASKAP Survey Science Projects
In 2009, after an open call for proposals, CSIRO announced that ten major science projects had been selected to use ASKAP. Of the ten projects’ authors, 33% were from Australia and New Zealand, 30% from North America, 28% from Europe, and 9% from elsewhere in the world.The ten ASKAP Survey Science Projects are:
- EMU: Evolutionary Map of the Universe http://www.atnf.csiro.au/people/rnorris/emu/
- WALLABY: Widefield ASKAP L-Band Legacy All-Sky Blind Survey http://www.atnf.csiro.au/research/WALLABY/
- FLASH: The First Large Absorption Survey in HI http://www.physics.usyd.edu.au/sifa/Main/FLASH/
- VAST: An ASKAP Survey for Variables and Slow Transients http://www.physics.usyd.edu.au/sifa/vast/index.php
- GASKAP: The Galactic ASKAP Spectral Line Survey http://sites.google.com/site/gaskapproject/home
- POSSUM: Polarization Sky Survey of the Universe's Magnetism http://www.physics.usyd.edu.au/sifa/possum/
- CRAFT: The Commensal Real-time ASKAP Fast Transients survey
- DINGO: Deep Investigations of Neutral Gas Origins http://internal.physics.uwa.edu.au/~mmeyer/dingo/welcome.html
- VLBI: The High Resolution Components of ASKAP: Meeting the Long Baseline Specifications for the SKA
- COAST: Compact Objects with ASKAP: Surveys and Timing