The search for alien life in space has once again turned to mysterious radio signals from distant stars. For years, so-called fast radio bursts (FRBs) have puzzled astronomers for years, with theories ranging from attempts at intergalactic communication or even that they might be powering some form of extraterrestrial spacecraft. While scores of these radio bursts have been recorded and their sources located, scientists still aren’t any closer to determining what (if anything) they might be signaling. Just this week, the search for radio communications in space got a huge boost thanks to the discovery of a new radio signal coming from right next door - cosmically speaking, that is.
On May 12th, astronomers at the Arecibo Observatory in Puerto Rico made famous in the Goldeneye James Bond film detected an odd radio signal coming from Ross 128, a red dwarf star located just eleven light years away in the Virgo constellation. The signal lasted for around ten minutes and was in a frequency band not typically heard in known natural phenomena.
Abel Mendez, director of the Planetary Habitability Laboratory (PHL) at the University of Puerto Rico, issued a press release describing the find and the three main theories his laboratory has put forth:
We believe that the signals are not local radio frequency interferences (RFI) since they are unique to Ross 128, and observations of other stars immediately before and after did not show anything similar. We do not know the origin of these signals but there are three main possible explanations: they could be (1) emissions from Ross 128 similar to Type II solar flares, (2) emissions from another object in the field of view of Ross 128, or just (3) burst from a high orbit satellite since low orbit satellites are quick to move out of the field of view.
Mendez is quick to note, however, that each of these theories has its holes. Solar flares typically emit frequencies quite different from the ones observed, and satellites aren’t known to emit radio bursts like the one recorded at Aricebo. While many outlets have been quick to jump on this radio signal as proof of an alien civilization, PHL scientists note that “the recurrent aliens hypothesis is at the bottom of many other better explanations." Bummer. Always is, though, isn't it?
Still, any discovery of radio signals are a step in the right direction, even if they end up being prosaic in origin. Learning how to discern naturally-occurring signals from what might be unnatural ones is all part of the ongoing narrative of our search for alien life. It’s got to be out there somewhere, right?