Statistically, it's pretty much a given that alien life is out there somewhere, whether that's Martian microbes or highly intelligent life beaming comms through the cosmos. While the Curiosity rover is poking around in the dirt for the former, the Breakthrough Listen initiative is searching for the latter. Now, a new telescope array has joined the hunt, scanning the skies for flashes of laser light that alien civilizations might be giving off.
The Breakthrough Listen initiative is the largest scientific program designed specifically to find evidence of extraterrestrials. The aim is to survey the million closest stars to Earth for any signs of radio and laser transmissions, which aliens might be using to communicate with each other or even deliberately broadcasting their existence. The team claims the tech is so powerful it can detect a laser with the energy of a regular light bulb from 25 trillion miles (40 trillion km) away.
And now the project has a new tool in its arsenal. The Very Energetic Radiation Imaging Telescope Array System (VERITAS) is made up of four 12-m (40-ft) telescopes, and was designed to detect gamma rays by the bursts of blue light they create as they hit the Earth's upper atmosphere.
As part of Breakthrough Listen, VERITAS will search for pulses of laser light that might be as short as a few nanoseconds. The idea is that if aliens are using lasers to communicate, Earth might just happen to cross the path of a rogue beam for a split second, alerting us to their presence even if that wasn't their direct intention.
"When it comes to intelligent life beyond Earth, we don't know where it exists or how it communicates," says Yuri Milner, founder of the Breakthrough Initiatives. "So our philosophy is to look in as many places, and in as many ways, as we can. VERITAS expands our range of observation even further."
VERITAS has already been put to work for similar goals. In the past, the array was trained on Tabby's Star, which has been mysteriously dimming at irregular intervals. While some sort of alien megastructure was one suggested explanation, the most likely culprit is still a cloud of comets. Nevertheless it pays to double-check, and no optical signals were detected.
VERITAS is a powerful addition to the cause, too. The team says that its telescopes could pick up a nanoseconds-long pulse from a laser as powerful as Earth's best, from the distance of Tabby's Star – 1,470 light-years away. Better news is the fact that most of the other stars in the survey are much closer, meaning signals 100 to 10,000 times fainter could be detected from those places.
"Breakthrough Listen is already the most powerful, comprehensive, and intensive search yet undertaken for signs of intelligent life beyond Earth," says Andrew Siemion, leader of the Listen team. "Now, with the addition of VERITAS, we're sensitive to an important new class of signals: fast optical pulses. Optical communication has already been used by NASA to transmit high definition images to Earth from the Moon, so there's reason to believe that an advanced civilization might use a scaled-up version of this technology for interstellar communication."
All we can do now is wait for ET to phone.
Source: UC Santa Cruz
