For twelve years, astronomers at the LPA radio telescope in Pushchino have been listening to the same patch of sky — the direction of the galaxy 3C 33. In that time, they caught just six short radio signals, each lasting from one to four minutes.
These bursts turned out to be extremely bright: their flux reached hundreds of janskys (a unit of radio source brightness, like lumens for a light bulb, but for radio waves). But the strangest part: they didn't repeat regularly and didn't resemble any known type of cosmic "radio explosion." The scientists ran through the possibilities (pulsars, stellar flares, active galactic nuclei) none fit.
So it seems we're dealing with a new type of celestial object. It produces rare but powerful radio bursts that last for minutes. What it could be remains a mystery. Perhaps it's some unusual process in a distant galaxy, or even a new class of cosmic bodies we never suspected before.
The LPA radio telescope in Pushchino is a field of thousands of dipole antennas, resembling a giant "comb" the size of 30 football fields. It picks up the lowest-frequency radio waves that almost no other telescope uses.