Harvard Scientists Suggest Mysterious Fast Radio Bursts Could Be Aliens

Fast radio bursts have always been one of the Universe's greatest unsolved mysteries. The existence of extraterrestrial life is another.

In a new paper published in Astrophysical Journal Letters, Harvard scientists proposed that the two might be related, suggesting that these radio bursts might be leakage from massive transmitters that power probes from other galaxies.

The strange phenomenon of fast radio bursts are simply flashes of radio emission that last for just a millisecond. It was first observed in 2007, but only 17 have ever been detected, according to a report from Gizmodo. Scientists estimate they came from far, far away, in galaxies billions of light-years in the distance.

"Fast radio bursts are exceedingly bright given their short duration and origin at great distances, and we haven't identified a possible natural source with any confidence," author Avi Loeb, theorist from the Harvard-Smithsonian Center for Astrophysics, explained in a report from Harvard University. "An artificial origin is worth contemplating and checking."

After all, scientists haven't identified a natural astronomical object that produces radio bursts at the intense brightness of fast radio bursts, which has a brightness temperature of 10³⁷ degrees.

The bursts' repetitive nature also points to an artificial source, since its unpredictable and concentrated on a specific frequency - not behavior expected from other sources like a star's collapse or a pulsar.

In the study, Loeb and co-author Manasvi Lingam from Harvard University studied the feasibility of a radio transmitter that could emit bursts detectable from billions of light-years away. The pair discovered that sunlight illuminating an area that's twice as big as Earth would generate enough solar energy to power such a transmitter.

While a transmitter like this is impossible at the moment with current human technology, Loeb and Lingam say it adheres to the known laws of physics.

The scientists also suggested a reason for the existence of a powerful transmitter like this, saying that the most plausible use for it is powering interstellar light sails. Such intense power is enough to drive an object 20 times the size of the biggest cruise ships on Earth.

Although the authors admit that their work is speculative, the insight from their findings is valuable.

"Science isn't a matter of belief, it's a matter of evidence," Loeb pointed out, when asked whether he truly believes aliens are behind the fast radio bursts. "Deciding what's likely ahead of time limits the possibilities. It's worth putting ideas out there and letting the data be the judge."