A cluster of structures spread across the deserts of Western Australia and South Africa is set to become the world’s largest radio observatory – and is expected to find evidence of extraterrestrial civilisations.
According to The Guardian, construction of the world’s largest radio astronomy observatory, called the Square Kilometer Array (SKA), has officially begun in Australia after three decades of preparation. The groundbreaking ceremony for the first segment of the entire system, SKA-Low in Australia, was held on December 5.
SKA is hailed as the largest scientific project of the century, developed by the Australian Government with the aim of helping scientists peer deep into space billions of light-years away to understand the early period of the universe’s history, when the first stars and galaxies formed.
It will also be used to learn about dark energy and why the universe is expanding. Another long-awaited goal is the search for extraterrestrial life.
According to Space, the SKA system will initially include two large telescope arrays, the SKA-Mid array, located in the Karoo Desert in South Africa, and the SKA-Low array, located in the Western Australian desert, north of Perth.
The SKA-Mid array in the Karoo will scan the sky for radio sources in the mid-frequency range of 350 MHz to 15.4 GHz using 197 dipole antennas, each 15 metres in diameter. The SKA-Low array in Australia will rely on 131,072 dipole antennas to detect radio waves with a frequency of 50 to 350 MHz.
Radio waves, which have much longer wavelengths than visible light, penetrate dust and debris, allowing astronomers to observe regions of space obscured by other types of observatories. That’s why radio observatories can see remote, hidden places that other types of observatories can’t.
According to Catherine Cesarsky, Chair of the Board of Directors of the SKA Observatory (SKAO), this space-based remote sensing facility will create a new revolution in astronomical research. It is also environmentally friendly as most of its energy comes from renewable resources.
Due to the extreme sensitivity of the antennas, the arrays must be placed in remote locations where the use of conventional radio receivers is prohibited to avoid signal interference.
The largest radio observatory in the world is currently ALMA, located in the Antacama Desert in Chile.