The international SKA project aims to construct the world’s largest radio telescope – around 50 times more sensitive than present instruments – by around 2025, with Phase 1 science commencing in 2020. The current detailed design phase (pre-construction) between 2013 and 2017 will see a ‘down-select’ of technologies for the first construction stage – SKA1.
The SKA will be an ultrasensitive radio telescope with a collecting area of up to a million square metres, purpose-built to further the understanding of the most important phenomena in the Universe. Over the next few years, the SKA project will transition from a formative concept to a fully operational instrument (SKA1) approximating 10% of the proposed full SKA2 instrument.
The SKA1 Observatory will comprise two components. SKA1_MID will be in the Karoo region of South Africa, with 200 dishes, incorporating the MeerKAT SKA precursor and equipped with single pixel feeds, and with a frequency range from 350 MHz to 14 GHz. SKA1_LOW, a sparse aperture low frequency array with 130,000 dipole antennas covering 50-350 MHz, will be built at the Murchison Radio astronomy Observatory (MRO) site in Western Australia, home of the Murchison Widefield Array (MWA) and ASKAP precursor telescopes.
Coming later, SKA2 will be a much larger array of coherently connected antennas spread over a continental scale, with an aggregate antenna collecting area of up to 106m2 at the longest wavelengths. As it evolves, the SKA will give astronomers insight into the formation and evolution of the first stars and galaxies after the Big Bang, the role of cosmic magnetism, the nature of gravity, and possibly even life beyond Earth.
More info and current status at www.skatelescope.org
The Low Frequency Aperture Array or ‘LFAA’ is the collecting element of the SKA1_LOW that is to be built at the MRO. The LFAA is being designed by a consortium of universities and research groups from Australia, the UK, the Netherlands and Italy including Cambridge University, Oxford University and the National Radio Astronomy Institutes of Italy and the Netherlands. This group is collectively known as the Aperture Array Design and Construction Consortium (AADC Consortium).
CIRA leads infrastructure design and planning, and the on-site prototyping and verification programs for the AADC Consortium. CIRA is also involved in the development of software correlation systems to support the verification of LFAA prototypes and verification systems.
Aperture Array Verification System 1 (AAVS1) is an LFAA prototype under construction by CIRA and its partners its international partners within the footprint of the MWA at the MRO. It will consist of up to 400 log-periodic dipole antennas and include at least one full size SKA_LOW field node—256 antennas deployed within a ~35m diameter. The AAVS will be employed principally as an engineering development and verification platform, but its co-location with MWA provides the opportunity to conduct interesting science with a hybrid array.
The AAVS also provides an opportunity for CIRA to trial and evaluate a variety of low-impact design and construction techniques that may be applicable to SKA_LOW.