Berkeley SETI turns Australian telescope on nearest exoplanet to Earth

Breakthrough Listen, the UC Berkeley-led 10-year, $100 million search for intelligent life beyond Earth, inaugurated its observations with the Parkes Radio Telescope in Australia by homing in on our nearest extrasolar planet, Proxima b, the main destination for a sister project called Breakthrough Starshot.

Launched in 2015 by internet entrepreneur Yuri Milner and physicist Stephen Hawking, Breakthrough Listen has been observing the Northern Hemisphere for nine months at the Green Bank Telescope in West Virginia. One of its targets includes the mysterious Tabby’s star, which some have speculated is host to an advanced civilization that has built massive structures around the star.

A team of scientists and engineers from UC Berkeley’s SETI Research Center deployed similar signal-processing hardware at the Parkes telescope in New South Wales, bringing Breakthrough Listen’s unprecedented search tools to a wide range of sky inaccessible from West Virginia, including the center of our Milky Way galaxy, large swaths of the galactic plane and numerous other galaxies in the nearby universe.

“The addition of Parkes is an important milestone,” said Yuri Milner, founder of the Breakthrough Initiatives, which include Breakthrough Listen. “These major instruments are the ears of planet Earth, and now they are listening for signs of other civilizations.”

After 14 days of commissioning and test observations, first light for Breakthrough Listen at Parkes was achieved on Nov. 7 with an observation of a newly discovered Earth-size planet orbiting the star nearest to Earth, Proxima Centauri. A red dwarf star 4.3 light-years from Earth, Proxima Centauri is now known to have a planet, designated Proxima b, within its habitable zone, the region where water could exist in liquid form on the planet’s surface.

Such “exo-Earths” (habitable zone exoplanets) are among the primary targets for Breakthrough Listen, and Proxima b is the primary target for Breakthrough Listen’s sister initiative, Breakthrough Starshot, which is developing the technology to send gram-size spacecraft to nearby stars.

“The chances of any particular planet hosting intelligent life-forms are probably minuscule,” said Andrew Siemion, director of UC Berkeley SETI Research Center. “But once we knew there was a planet right next door, we had to ask the question, and it was a fitting first observation for Parkes. To find a civilization just 4.2 light years away would change everything.”

The Parkes radio telescope is part of the Australia Telescope National Facility, owned and managed by Australia’s Commonwealth Scientific and Industrial Research Organization, or CSIRO.

“Parkes’ unique view of the southern sky, and cutting-edge instrumentation, means we have a great opportunity to contribute to the search for extraterrestrial life,” said Douglas Bock, Director of CSIRO Astronomy and Space Science.

Breakthrough Listen also looks for optical signals from other civilizations using the Automated Planet Finder at the University of California’s Lick Observatory near San Jose, California. On Oct. 12, the project announced it will be joining forces with the new FAST telescope in China – the world’s largest filled-aperture radio receiver – to coordinate their searches for artificial signals. The partnership represents a major step toward establishing a fully connected, global search for intelligent life in the universe.