For the first time, astronomers have detected radio signals coming directly from a planet outside our solar system, according to a new preprint study. Spoiler alert: It's not aliens. But astrophysicists are still very excited about this discovery. "Astronomers have been looking for radio signals from exoplanets for some time," Suzanne Aigrain, a professor of astrophysics at the University of Oxford who was not involved in the study, told Live Science in an email. "There have been tentative, indirect detections before, but this is the first truly convincing direct detection, and it hopefully paves the way for many more."Artificial radio signals are a key focus in the search for extraterrestri...