An artists's concept of what a deployed solar sail space probe may look like. One capturing the power inferred by mysterious fast radio bursts would be on the scale of several planets.

Fast radio bursts are mysterious flashes from deep space that last just a few milliseconds.

They were first seen in 2007.

Since then, about a dozen have been detected by the world’s larger radio telescopes, such as the Parkes Observatory in New South Wales.

Scientists have been scratching their heads as to where they could possibly come from ever since.

A question without an easy answer? Therefore aliens.

Alien megastructures, anyone?

“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,” says Harvard-Smithsonian Center for Astrophysics theorist Avi Loeb in a statement.

“An artificial origin is worth contemplating and checking.”

He’s one of the authors of a study published in Astrophysical Journal Letters.

They set out to determine what it would take to create a radio burst strong enough to flash across billions of light years of space.

One such example, they surmised, could be a solar-powered transmitter with a surface area twice the size of the Earth.

Such a machine would involve an enormous construction effort.

But still nowhere near the interplanetary size of the alien megastructure proposed as an explanation for giving the star KIC 8462852 its strange stutter.

And there could be a very strong reason to build such a device.

Interstellar travel.

The raw power contained in such a focused radio stream would be enough to propel a 1-million-tonne ship over interstellar distances, they say.

At 20 times bigger than the largest ocean liner, “that’s big enough to carry living passengers across interstellar or even intergalactic distances,” co-author Manasvi Lingam of Harvard University stated.

So why do we see only a flash?

Such a ship would likely need the radio beam to be blasting into its sails constantly.

The researchers say all things are relative.

The sail-ship is moving. Its host planet is moving. Its star is moving.

This means the radio beams would only occasionally sweep past our direction.

Is this all just pie-in-the-sky thinking?

“Science isn’t a matter of belief, it’s a matter of evidence,” Loeb says.

“Deciding what’s likely ahead of time limits the possibilities. It’s worth putting ideas out there and letting the data be the judge.”

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