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Sci-Tech

Have you given up on alien life? Scientists haven't

The search for extraterrestrial intelligence is the stuff of science fiction, but turns out the real scientists are invested too.

trappist-1f-exoplanet-nasa

NASA believes exoplanets like TRAPPIST-1f could have the right conditions for liquid water, meaning they could support life.

NASA/JPL-Caltech

Whether you grew up in the '60s under a cloud of Area 51 conspiracies or you were a '90s alternative kid with a die-hard love of David Duchovny, you've probably entertained theories about alien life.

But turns out, you're not alone. (In your wild theorizing, that is, not "not alone in the universe." We could very well be the only ones here, so if you're the last one to survive, please turn out the lights.)

The search for extraterrestrial intelligence (also known as SETI) has been a serious pursuit of modern scientists as far back as the early 1900s, when Guglielmo Marconi first claimed to pick up radio signals "seeming to come from beyond the Earth." (Nikolai Tesla suggested they could be from Mars -- thanks, Nik.)

Over the years, the search has only intensified. 

On this week's episode of Watch This Space, we take a look at the entirely scientific, entirely credible search for extraterrestrial intelligence being undertaken by scientists, astronomers and researchers around the world.

Now playing: Watch this: Aliens and the search for extraterrestrial intelligence
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So, failing some kind of alien mothership landing on our planet, how do we search for proof? There's a few key ways to do it.

Messages from afar

Just like Marconi imagined, it's possible that we could pick up radio signals from distant planets and finally find out the truth about our (very, very distant) neighbours. Back in 1977, astronomer Jerry Ehman was picking through data from Ohio's "Big Ear" radio telescope when he found a radio signal lasting roughly 1 minute. Its origin still remains a mystery, but it's known as the "WOW Signal" for the word Ehman wrote in the margins of his reading printout.

The California-based SETI Institute is continuing this work. One of the leading agencies in the field of SETI research, the SETI Institute has a team of more than 80 researchers working across fields such as astronomy and astrobiology, and they continue to search for radio signals using their Allen Telescope Array located in California's Cascade Mountains. The Institute says we could well find signs of extraterrestrial intelligence in the next two decades.

Exoplanets

So how do we choose where to point our telescopes? Well, the most likely candidates for life outside our solar system are exoplanets -- they're planets that orbit stars like our sun where conditions (such as the availability of surface water) could make them ripe for life.

The now-retired Kepler Space Telescope and the new Transiting Exoplanet Survey Satellite (TESS) have hunted out these exoplanets by pointing toward stars and looking for dips in their brightness. If a star is bright and then dims before becoming bright again, it could be a sign that a planet is orbiting that star. We've found hundreds of exoplanets this way, including a raft of Earth-like planets that could well support life.

Secret programs and wild conspiracies

It wouldn't be a search for alien life if we didn't look at the crazy programs launched by government agencies over the years. 

Back in 2017, the New York Times revealed that the Pentagon had been working on a secret UFO program, funded to the tune of $22 million by the federal government. While the Department of Defense decided to defund the Advanced Aerospace Threat Identification Program in 2012, it reportedly still exists.

Then in April 2019, Politico reported that the US Navy is working on procedures for reporting unidentified aircraft, though the Navy said it wouldn't be making the results of this program public.

While the secret details of Area 51 have now been declassified and many conspiracy theories remain just that -- theories -- there are still plenty of organisations showing a keen interest in what lies beyond our solar system. All that's left to do is find what's out there.