Proxima Centauri and the space signal: Was that a dropped call from ET? 1 Jan, 2021 01:19 AM 8 minutes to read Alpha and Beta Centauri, photographed from Atacama Lodge, Chile. Proxima Centauri - the closest known star to the sun - is part of Alpha Centauri. Photo / Getty Images Alpha and Beta Centauri, photographed from Atacama Lodge, Chile. Proxima Centauri - the closest known star to the sun - is part of Alpha Centauri. Photo / Getty Images New York Times By: Dennis Overbye Nobody believes it was ET phoning, but radio astronomers admit they do not have an explanation yet for a beam of radio waves that apparently came from the direction of the star Proxima Centauri.