In 2007, astronomers detected a radio signal from the sky that was unlike any seen before. It lasted only a millisecond but was extremely bright. Even more unexpectedly, its characteristics implied that it arrived from an unidentified galaxy billions of light-years away. This type of explosion, more powerful than anything ever observed at similar wavelengths and timescales, is now termed a Fast Radio Burst (FRB).
During the last decades, astronomers have reported the existence of more FRBs, which have become one of the hottest topics in astronomy. They seem to be a common phenomenon; astronomers have detected more than 100 FRBs, and some estimates are that thousands reach Earth every day.
However, we still don’t understand what causes these powerful explosions. They are tremendously energetic, and the flashes come from billions of light-years away, and something over there can muster sufficient energy to produce a signal detectable here on Earth. Could these signals be due to aliens?
