The researchers propose to create a "beacon" which will be visible at a distance 20 thousand light years.
Clark said the megawatt laser could send Morse code signals to alien astronomers living in systems closest to the Earth such as Proxima Centauri or TRAPPIST-1, a star 40 light years away with three potentially habitable exoplanets.
A message sent in this manner would have a data rate of a few hundred bits per second and could arrive at the distant planet in a few years.More news: Trump says he did not discuss Russian Federation probe with acting attorney general
The notion of such an alien-attracting beacon may seem far-fetched, but Clark says the feat can be realized with a combination of technologies that exist now and that could be developed in the near term.
"This would be a challenging project but not an impossible one. I don't know if intelligent creatures around the sun would be their first guess, but it would certainly attract further attention". Clark emphasizes that if this laser be seen by alien astronomers, they can use the same technology to communicate with the inhabitants of the Earth. In the conclusion of the study, the experts are optimistic because they highlight that "withthe technology and the facilities existing or to come over the next decade, humanity is capable of producing a signal detectable despite the presence of the Sun".
In what author James Clark calls a "feasibility study", he proposes that a high-powered 1-to 2-megawatt laser be focused directly into space. While the Earth has been sending signals like radio waves into space for over a century, like those famously seen in the opening of Contact, it's possible that solar entities like the sun and exoplanets beyond the solar system have been interfering with signals, making it harder for potential aliens to touch base. Either setup, he estimated, could produce a generally detectable signal from up to 20,000 light-years away.More news: Walmart is doing Black Friday the earliest in its history
Assuming alien astronomers have comparable telescopes, they would need to be in the emission's exact line of sight which, statistically speaking, is pretty unlikely. He compares it to the Air Force's Airborne Laser program, known as the YAL-1, a prototype from the Reagan era which consisted of a 747 with a giant laser grafted onto the nose, meant to shoot down ballistic missiles. Clark also suggests building the apparatus atop a mountain where it would encounter less atmosphere before reaching space.
And despite the beam being invisible to the naked eye, it would still emit 800 watts of power per square meter, which could cause vision damage if it's looked at directly. A safer location than Earth would be on the far side of the moon.
He says the research was a primarily a "feasibility study", whether or not it's actually a good idea, he says, is a "discussion for future work".More news: Scientists Create 'Bionic Mushroom' That Can Generate Electricity
Having established that a planetary beacon is technically feasible, Clark then flipped the problem and looked at whether today's imaging techniques would be able to detect such an infrared beacon if it were produced by astronomers elsewhere in the galaxy.