Powerful new radio telescope gets close
The face of cosmology and astrophysics will change when the next-generation multi-purpose radio telescope known as the Square Kilometre Array (SKA) is completed. The EU-funded PREPSKA (A preparatory phase proposal for the Square Kilometre Array) project marked the launch of this ambitious endeavour. Addressing key issues such as design, location, legal framework, funding and cost effectiveness, the project outlined the three phases of construction required to deliver this state-of-the-art radio interferometer. It prepared comprehensive deployment and implementation plans that represent the basis for a funding proposal so that governments can begin construction of the SKA. The instrument will boast a frequency range from 70 MHz to over 25 GHz and a collecting area of over 1 million square metres, rendering it 50 times more sensitive than the most powerful radio telescope in existence. It will be superior in survey speed, image fidelity and resolution, and is destined to transform the field of astronomy. The first of three building phases will represent 10 % of the Array at low and mid-band frequencies, while the second will feature the full collecting area at the same frequencies. The third phase will cover implementation of the higher frequencies — i.e. up to 25 GHz or more. After careful study, the project chose two sites to host the antennas and dishes of the Array, namely South Africa and Western Australia. It completed the required concept design reviews and presented them to industry experts and the astronomical community, preparing the ground for the pre-construction phase. The design reviews addressed all sub-systems and the SKA system overall, including dishes, aperture arrays and digital processing technology. Apart from design, this work involved articulating the legal framework and governance structure for operation, identifying the most cost-effective strategy for procuring SKA components and defining funding mechanisms. This also involved the establishment of a legal entity for the global SKA Organisation and coordination on financing by funding agencies and governments in seven countries. This multi-purpose radio telescope covering the frequency range from 70 MHz to >25 GHz will be instrumental in answering key questions related to modern astrophysics and cosmology. The SKA will represent one of the cornerstone observatories across the electromagnetic spectrum that will provide astrophysicists and cosmologists with a transformational view of the Universe.
Keywords
Radio telescope, cosmology, astrophysics, Square Kilometre Array, electromagnetic spectrum
