MeerKAT
Encyclopedia
MeerKAT is a radio telescope
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...

 under construction in the Northern Cape
Northern Cape
The Northern Cape is the largest and most sparsely populated province of South Africa. It was created in 1994 when the Cape Province was split up. Its capital is Kimberley. It includes the Kalahari Gemsbok National Park, part of an international park shared with Botswana...

 of South Africa
South Africa
The Republic of South Africa is a country in southern Africa. Located at the southern tip of Africa, it is divided into nine provinces, with of coastline on the Atlantic and Indian oceans...

. It will be the largest and most sensitive radio telescope in the southern hemisphere until the Square Kilometer Array is completed around 2024.The telescope will be used for research into cosmic magnetism, galactic evolution
Galaxy formation and evolution
The 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...

, the large-scale structure of the cosmos, dark matter
Dark matter
In astronomy and cosmology, dark matter is matter that neither emits nor scatters light or other electromagnetic radiation, and so cannot be directly detected via optical or radio astronomy...

 and the nature of transient radio sources. It will also serve as a technology demonstrator for South Africa
South Africa
The Republic of South Africa is a country in southern Africa. Located at the southern tip of Africa, it is divided into nine provinces, with of coastline on the Atlantic and Indian oceans...

's bid to host the Square Kilometer Array. A MeerKAT engineering test bed of seven dishes (KAT-7) is already complete on site. The construction and commissioning of the full MeerKAT array will follow.

Technical Specifications

MeerKAT will consist of 64 dishes of 13.5 metres in diameter each with an offset Gregorian
Gregorian telescope
The Gregorian telescope is a type of reflecting telescope designed by Scottish mathematician and astronomer James Gregory in the 17th century, and first built in 1673 by Robert Hooke...

 configuration. An offset dish configuration has been chosen because its unblocked aperture provides uncompromised optical performance and sensitivity, excellent imaging quality and good rejection of unwanted radio frequency interference from satellites and terrestrial transmitters. It also facilitates the installation of multiple receiver systems in the primary and secondary focal areas and is the reference design for the mid-band SKA concept.

MeerKAT supports a wide range of observing modes, including deep continuum, polarisation and spectral line
Spectral line
A spectral line is a dark or bright line in an otherwise uniform and continuous spectrum, resulting from a deficiency or excess of photons in a narrow frequency range, compared with the nearby frequencies.- Types of line spectra :...

 imaging, pulsar timing and transient searches. A range of standard data products are provided, including an imaging pipeline. A number of "data spigots" are also available to support user-provided instrumentation. Significant design and qualification efforts are planned to ensure high reliability in order to achieve low operational cost and high availability.
Technical Specifications
Number of antennae 64
Dish diameter 13.5 m
Minimum baseline 29 m
Maximum baseline 20 km
Frequency bands (receivers) 0.58 – 1.015 GHz
1 – 1.75 GHz
8 – 14.5GHz
Continuum imaging dynamic range at 1.4 GHz 60 dB
Line-to-line dynamic range at 1.4 GHz 40 dB
Mosaicing imaging dynamic range at 1.4 GHz 27 dB
Linear polarisation cross coupling across -3 dB beam -30 dB


MeerKAT's 64 dishes will be distributed over two components:
  • A dense inner component containing 70% of the dishes. These are distributed in a two-dimensional fashion with a Gaussian uv-distribution with a dispersion of 300 m, a shortest baseline of 29 m and a longest baseline of 1 km.
  • An outer component containing 30% of the dishes. These are also distributed in a two-dimensional Gaussian uv-distribution with a dispersion of 2 500 m and a longest baseline of 8 km.


For Phase 2, seven additional antennae will be added to extend the longest baselines to about 20 km.

Construction Schedule

To build experience in the construction of interferometric telescopes, members of the Karoo Array Telescope constructed the Phased Experimental Demonstrator (PED) at the South African Astronomical Observatory
South African Astronomical Observatory
South African Astronomical Observatory is the national center for optical and infrared astronomy in South Africa. It was established in 1972. The observatory is run by the National Research Foundation of South Africa. The facility's function is to conduct research in astronomy and astrophysics...

 in Cape Town
Cape Town
Cape Town is the second-most populous city in South Africa, and the provincial capital and primate city of the Western Cape. As the seat of the National Parliament, it is also the legislative capital of the country. It forms part of the City of Cape Town metropolitan municipality...

 between 2005 and 2007.

During 2007 the 15 metres (49.2 ft) eXperimental Development Model Telescope (XDM) was built at the Hartebeesthoek Radio Astronomy Observatory
Hartebeesthoek Radio Astronomy Observatory
The Hartebeesthoek Radio Astronomy Observatory is a radio astronomy observatory located in a natural bowl of hills at Hartebeesthoek just south of the Magaliesberg mountain range, Gauteng, South Africa, about 50 km west of Johannesburg...

 to serve as a testbed for MeerKAT.

Construction of the MeerKAT Precursor Array (MPA - also known as KAT-7), on the Northern Cape
Northern Cape
The Northern Cape is the largest and most sparsely populated province of South Africa. It was created in 1994 when the Cape Province was split up. Its capital is Kimberley. It includes the Kalahari Gemsbok National Park, part of an international park shared with Botswana...

 site started in August 2009. The first seven dishes are complete. In April 2010 four of the seven dishes were linked together as an integrated system to produce its first interferometric image of an astronomical object. In Dec 2010, there was a successful detection of very long baseline interferometry (VLBI) fringes between the Hartebeesthoek Radio Astronomy Observatory 26 m dish and one of the KAT-7 dishes.

MeerKAT will be delivered in three phases. The commissioning of MeerKAT will take place in 2014 and 2015 with the array coming online for science operations in 2016. This phase will include all the antennae but only the first receiver will be fitted. A processing bandwidth of 750 MHz will be available. For the second and third phases the remaining two receivers will be fitted and the processing bandwidth will be increased to at least 2 GHz, with a goal of 4 GHz.
MeerKAT Phasing Schedule
2011
Precursor (KAT-7)
2016
MeerKAT Phase 1
2018
MeerKAT Phase 2 and 3
Number of dishes 7 64 64
Receiver bands (GHz) 0.9 – 1.6 1.00 – 1.75 0.58 – 1.015
1.00 – 1.75
8 – 14.5
Max processed BW (GHz) 0.256 0.75 2 (goal 4)
Max baseline (km) 0.2 8 20
Min baseline (m) 20 29 29

MeerKAT Science

Five years of observing time on MeerKAT have been allocated to leading astronomers who have applied for time to do research. The science objectives of the MeerKAT surveys are in line with the prime science drivers for the first phase of the SKA, confirming MeerKAT's designation as an SKA precursor instrument.
Science Projects Research Leaders
Testing Einstein's theory of gravity
Gravitation
Gravitation, or gravity, is a natural phenomenon by which physical bodies attract with a force proportional to their mass. Gravitation is most familiar as the agent that gives weight to objects with mass and causes them to fall to the ground when dropped...

 and gravitational radiation – Investigating the physics of enigmatic neutron stars through observations of pulsars.
Prof Matthew Bailes, Swinburne Centre for Astrophysics and Supercomputing
Centre for Astrophysics and Supercomputing
The Centre for Astrophysics and Supercomputing is a research centre located at the Swinburne University in Melbourne, Australia.The Centre comprises about 20 staff and students engaged in diverse areas of astrophysical research. It is actively involved in the planned Square Kilometre Array...

, Australia
LADUMA (Looking At the Distant Universe with the MeerKAT Array) – An ultra-deep survey of neutral hydrogen gas in the early universe. Dr Sarah Blyth, University of Cape Town
University of Cape Town
The University of Cape Town is a public research university located in Cape Town in the Western Cape province of South Africa. UCT was founded in 1829 as the South African College, and is the oldest university in South Africa and the second oldest extant university in Africa.-History:The roots of...

, South Africa
Dr Benne Holwerda, European Space Agency
European Space Agency
The European Space Agency , established in 1975, is an intergovernmental organisation dedicated to the exploration of space, currently with 18 member states...

, The Netherlands
Dr Andrew Baker, Rutgers University
Rutgers University
Rutgers, The State University of New Jersey , is the largest institution for higher education in New Jersey, United States. It was originally chartered as Queen's College in 1766. It is the eighth-oldest college in the United States and one of the nine Colonial colleges founded before the American...

, United States
MESMER (MeerKAT Search for Molecules in the Epoch of Reionization) – Searching for CO at high red-shift (z>7) to investigate the role of molecular hydrogen in the early universe. Dr Ian Heywood, University of Oxford
University of Oxford
The University of Oxford is a university located in Oxford, United Kingdom. It is the second-oldest surviving university in the world and the oldest in the English-speaking world. Although its exact date of foundation is unclear, there is evidence of teaching as far back as 1096...

, United Kingdom
MeerKAT Absorption Line Survey for atomic hydrogen and OH lines in absorption against distant continuum sources (OH line ratios may give clues about changes in the fundamental constants in the early universe). Dr Neeraj Gupta, ASTRON
ASTRON
ASTRON is the Netherlands Foundation for Research in Astronomy. ASTRON is an abbreviation of the Dutch Stichting ASTRonomisch Onderzoek in Nederland. This translates to NFRA in English, which is sometimes used to refer to ASTRON in English texts. Its main offices are in Dwingeloo at the site of the...

, The Netherlands
Dr Raghunathan Srianand, Inter-University Centre for Astronomy and Astrophysics
Inter-University Centre for Astronomy and Astrophysics
The Inter-University Centre for Astronomy and Astrophysics is an autonomous institution set up by the University Grants Commission to promote nucleation and growth of active groups in astronomy and astrophysics in Indian universities...

, India
MHONGOOSE (MeerKAT HI Observations of Nearby Galactic Objects: Observing Southern Emitters) – Investigations of different types of galaxies, dark matter
Dark matter
In astronomy and cosmology, dark matter is matter that neither emits nor scatters light or other electromagnetic radiation, and so cannot be directly detected via optical or radio astronomy...

 and the cosmic web.
Prof Erwin de Blok, University of Cape Town
University of Cape Town
The University of Cape Town is a public research university located in Cape Town in the Western Cape province of South Africa. UCT was founded in 1829 as the South African College, and is the oldest university in South Africa and the second oldest extant university in Africa.-History:The roots of...

, South Africa
TRAPUM (Transients and Pulsars with MeerKAT) – Searching for and investigating new and exotic pulsars. Dr Benjamin Stappers, Jodrell Bank Centre for Astrophysics
Jodrell Bank Centre for Astrophysics
The Jodrell Bank Centre for Astrophysics at the University of Manchester, is among the largest astrophysics groups in the UK. It includes the world leading facilities of the Jodrell Bank Observatory, the MERLIN/VLBI National Facility, the Development Office of the Square Kilometre Array, and the...

, United Kingdom
Prof Michael Kramer, Max Planck Institute for Radio Astronomy
Max Planck Institute for Radio Astronomy
The Max Planck Institute for Radio Astronomy is located in Bonn, Germany. It is one of 80 institutes in the Max Planck Society .-History:...

, Germany
A MeerKAT HI Survey of the Fornax Cluster
Fornax Cluster
At a distance of approximately 62.0 Mly , the Fornax Cluster is the second richest cluster of galaxies within 100 million light-years, although it is much smaller than the Virgo Cluster. It lies primarily in the constellation Fornax, and may be associated with the nearby Eridanus Group...

 (Galaxy formation and evolution in the cluster environment).
Dr Paolo Serra, ASTRON
ASTRON
ASTRON is the Netherlands Foundation for Research in Astronomy. ASTRON is an abbreviation of the Dutch Stichting ASTRonomisch Onderzoek in Nederland. This translates to NFRA in English, which is sometimes used to refer to ASTRON in English texts. Its main offices are in Dwingeloo at the site of the...

, The Netherlands
MeerGAL (MeerKAT High Frequency Galactic Plane
Galactic plane
The galactic plane is the plane in which the majority of a disk-shaped galaxy's mass lies. The directions perpendicular to the galactic plane point to the galactic poles...

 Survey) – Galactic structure and dynamics, distribution of ionised gas, recombination lines, interstellar molecular gas and masers
Astrophysical maser
An astrophysical maser is a naturally occurring source of stimulated spectral line emission, typically in the microwave portion of the electromagnetic spectrum...

.
Dr Mark Thompson, University of Hertfordshire
University of Hertfordshire
The University of Hertfordshire is a new university based largely in Hatfield, in the county of Hertfordshire, England, from which the university takes its name. It has more than 27,500 students, over 2500 staff, with a turnover of over £181m...

, United Kingdom
Dr Sharmila Goedhart, SKA South Africa, South Africa
MIGHTEE (MeerKAT International GigaHertz Tiered Extragalactic Exploration survey) – Deep continuum observations of the earliest radio galaxies. Dr Kurt van der Heyden, University of Cape Town
University of Cape Town
The University of Cape Town is a public research university located in Cape Town in the Western Cape province of South Africa. UCT was founded in 1829 as the South African College, and is the oldest university in South Africa and the second oldest extant university in Africa.-History:The roots of...

, South Africa
Dr Matt Jarvis, University of the Western Cape
University of the Western Cape
The University of the Western Cape is a public university located in the Bellville suburb of Cape Town, South Africa. It was established in 1960 by the South African government as a university for Coloured people only...

, South Africa and the University of Hertfordshire
University of Hertfordshire
The University of Hertfordshire is a new university based largely in Hatfield, in the county of Hertfordshire, England, from which the university takes its name. It has more than 27,500 students, over 2500 staff, with a turnover of over £181m...

, United Kingdom
ThunderKAT (The Hunt for Dynamic and Explosive Radio Transients with MeerKAT) – e.g. gamma-ray bursts, novae
Nova
A nova is a cataclysmic nuclear explosion in a star caused by the accretion of hydrogen on to the surface of a white dwarf star, which ignites and starts nuclear fusion in a runaway manner...

 and supernovae
Supernova
A supernova is a stellar explosion that is more energetic than a nova. It is pronounced with the plural supernovae or supernovas. Supernovae are extremely luminous and cause a burst of radiation that often briefly outshines an entire galaxy, before fading from view over several weeks or months...

, plus new types of transient radio sources.
Prof Patrick Woudt, University of Cape Town
University of Cape Town
The University of Cape Town is a public research university located in Cape Town in the Western Cape province of South Africa. UCT was founded in 1829 as the South African College, and is the oldest university in South Africa and the second oldest extant university in Africa.-History:The roots of...

, South Africa
Prof Rob Fender, University of Southampton
University of Southampton
The University of Southampton is a British public university located in the city of Southampton, England, a member of the Russell Group. The origins of the university can be dated back to the founding of the Hartley Institution in 1862 by Henry Robertson Hartley. In 1902, the Institution developed...

, United Kingdom


MeerKAT will also participate in global VLBI operations with all major radio astronomy observatories around the world and will add considerably to the sensitivity of the global VLBI network. Further potential science objectives for MeerKAT are to participate in the search for extra-terrestrial intelligence and collaborate with NASA
NASA
The National Aeronautics and Space Administration is the agency of the United States government that is responsible for the nation's civilian space program and for aeronautics and aerospace research...

 on downloading information from space probes.

See also

  • Square Kilometer Array
  • Australian Square Kilometre Array Pathfinder
    Australian Square Kilometre Array Pathfinder
    The Australian Square Kilometre Array Pathfinder, or ASKAP, is CSIRO’s new radio telescope currently under construction at the Murchison Radio-astronomy Observatory in Mid West region of Western Australia...

  • Hartebeesthoek Radio Astronomy Observatory
    Hartebeesthoek Radio Astronomy Observatory
    The Hartebeesthoek Radio Astronomy Observatory is a radio astronomy observatory located in a natural bowl of hills at Hartebeesthoek just south of the Magaliesberg mountain range, Gauteng, South Africa, about 50 km west of Johannesburg...

  • List of radio telescopes
  • South African Astronomical Observatory
    South African Astronomical Observatory
    South African Astronomical Observatory is the national center for optical and infrared astronomy in South Africa. It was established in 1972. The observatory is run by the National Research Foundation of South Africa. The facility's function is to conduct research in astronomy and astrophysics...

     for optical astronomy in South Africa
    South Africa
    The Republic of South Africa is a country in southern Africa. Located at the southern tip of Africa, it is divided into nine provinces, with of coastline on the Atlantic and Indian oceans...

  • Precision Array for Probing the Epoch of Reionization
    Precision Array for Probing the Epoch of Reionization
    The Precision Array for Probing the Epoch of Reionization is a radio interferometer designed to detect 21 cm Hydrogen fluctuations occurring when the first galaxies ionized intergalactic gas at around 500 Million years after the Big Bang....


External links

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