From Our Archives: How We've Searched For Alien Life

Just looking for some interplanetary friends

The October 1984 cover of Popular Science with radio telescopes

October 1984

Popular Science

In October 1984, Popular Science wrote about one of the more promising chapters in the search for intelligent life. NASA was set to embark on a 15-year mission: An 85-foot-tall radio tele­scope would filter out the torrent of chaotic radio signals it received while it scanned the universe, "seeking the one unambiguous pattern that would signify something totally extraordinary," we wrote. Sadly, those efforts didn't yield much, and today NASA is focused on finding any life--intelligent or no. In the decade to come, the agency plans to send a spacecraft to Jupiter's moon Europa, which could possibly harbor life beneath its icy surface. To learn more, click here.

How to Spot An Alien

Gamma-Ray Bursts

In 1995, a scientist at MIT Haystack Observatory proposed that extraterrestrials might communicate with gamma rays. Since then, the Fermi Gamma-ray Space Telescope has been on the lookout.

Technosignatures

Since 2005, Fermilab in Illinois has been surveying the universe for city lights, atmospheric contamination, or any other infrared sources that could indicate the use of advanced technology.

Optical Experiments

A Harvard-Smithsonian group is building a 72-inch telescope to detect powerful lasers, in case extraterrestrials use them to communicate.

Biosignatures

The new James Webb Space Telescope, set to launch in 2018, will search for exoplanets, but also for signs of life--oxygen and methane--in their atmospheres.

This article was originally published in the September 2015 issue of Popular Science, under the title "Is Anybody Out There?"