On Aug. 15, 1977, astronomers using Ohio State University's Big Ear radio telescope detected the famous "Wow!" signal, which to this day is one of the strongest pieces of evidence that we are not alone in the universe.
Astronomer Jerry Ehman was using the telescope to scan a region in the constellation Sagittarius when it detected a weird, 72-second-long radio burst. The signal was too strong to be explained by background noise, and researchers determined that it was very unlikely that this signal came from anything on Earth.
Despite their best efforts, astronomers have not been able to detect any other signals like it.
Why it mattered
For as long as humans have existed, we have looked up and wondered, "Are we alone?" This question remains one of the biggest mysteries across not just science but for humanity as a whole. The "Wow" signal remains an iconic and important finding in the search for life out in the cosmos.
Nearly 50 years since the "Wow!" signal, scientists have made incredible progress in the search for alien life. We have landed rovers on Mars that have found possible signs of life on the Red Planet, for example, and discovered thousands of exoplanets, or planets outside of our solar system.
The "Wow!" signal was detected nearly two decades before scientists first confirmed the existence of exoplanets. Today, we have found more than 6,000 of them and are using cutting-edge technologies to explore further and see if any of these far-off planets might contain signs of life.
Hanneke Weitering is a multimedia journalist in the Pacific Northwest reporting on the future of aviation at FutureFlight.aero and Aviation International News and was previously the Editor for Spaceflight and Astronomy news here at Space.com. As an editor with over 10 years of experience in science journalism she has previously written for Scholastic Classroom Magazines, MedPage Today and The Joint Institute for Computational Sciences at Oak Ridge National Laboratory. After studying physics at the University of Tennessee in her hometown of Knoxville, she earned her graduate degree in Science, Health and Environmental Reporting (SHERP) from New York University. Hanneke joined the Space.com team in 2016 as a staff writer and producer, covering topics including spaceflight and astronomy. She currently lives in Seattle, home of the Space Needle, with her cat and two snakes. In her spare time, Hanneke enjoys exploring the Rocky Mountains, basking in nature and looking for dark skies to gaze at the cosmos.