Mysterious Energy Signals Called “Fast Radio Bursts” Come From Outer Space, Scientists Confirm

Image credit: M. Weiss/Center for Astrophysics

In 2007, a West Virginia University astrophysicist named Duncan Lorimer detected a brief yet very strong burst of radio emission coming from an unidentified source in space while combing through archival data from the Parkes Observatory telescope in Australia.

Lorimer’s discovery introduced us to a new class of objects dubbed “fast radio bursts” or FRBs.

The detection, also known as the Lorimer burst, was the first discovery of its kind.

Since then, astronomers have stumbled upon 17 more FRBs, and their source has mystified scientists for years.

Everyday Einstein explains the name:

“Fast” because these blips are very short—less than 5 milliseconds in duration. So chop one second into a thousand parts and you’re looking at less than five of your pieces.

The “radio” portion of the moniker is due to the fact that the emission is detected by radio telescopes surveying the sky at radio wavelengths. They are called “bursts” because the signals disappear as quickly as they appeared, without warning and, so far, without explanation.

FRBs are some of the most elusive and explosive signals ever detected in space, and while they last for mere milliseconds, they generate as much energy as 500 million Suns. They are about a billion times more luminous than anything we have ever seen in our own Milky Way galaxy.

Last year, researchers found 16 FRBs all coming from the same source beyond our Milky Way, reports Science Alert.

And, last month, Harvard physicists proposed that signals like these could be evidence of advanced alien technology:

The search for extraterrestrial intelligence has looked for many different signs of alien life, from radio broadcasts to laser flashes, without success. However, newly published research suggests that mysterious phenomena called fast radio bursts could be evidence of advanced alien technology. Specifically, these bursts might be leakage from planet-sized transmitters powering interstellar probes in distant galaxies.

“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,” said theorist Avi Loeb of the Harvard-Smithsonian Center for Astrophysics. “An artificial origin is worth contemplating and checking.”

More from Harvard’s press release:

Loeb and his co-author Manasvi Lingam (Harvard University) examined the feasibility of creating a radio transmitter strong enough for it to be detectable across such immense distances. They found that, if the transmitter were solar powered, the sunlight falling on an area of a planet twice the size of the Earth would be enough to generate the needed energy. Such a vast construction project is well beyond our technology, but within the realm of possibility according to the laws of physics.

Lingam and Loeb also considered whether such a transmitter would be viable from an engineering perspective, or whether the tremendous energies involved would melt any underlying structure. Again, they found that a water-cooled device twice the size of Earth could withstand the heat.

They then asked, why build such an instrument in the first place? They argue that the most plausible use of such power is driving interstellar light sails. The amount of power involved would be sufficient to push a payload of a million tons, or about 20 times the largest cruise ships on Earth.

“That’s big enough to carry living passengers across interstellar or even intergalactic distances,” added Lingam.

What ARE light sails? Science Alert explains:

If you’re not familiar with lightsails, the technology is still in its infancy – at least, on Earth – but has the potential to revolutionize space exploration, with NASA researchers estimating that we could get one to Mars in three days flat.

Known as ‘photonic propulsion’ systems, lightsails are powered by the momentum of photons (particles of light), which could either be harnessed from the Sun’s rays, like Bill Nye’s light sail, or giant Earth-based lasers, like this NASA proposal.

That means virtually zero fuel would be required, and journeys could last as long as the physical parts could hold.

This video explains light sails in more detail.

Loeb admits that this work is speculative. When asked whether he really believes that any fast radio bursts are due to aliens, he replied,

“Science isn’t a matter of belief, it’s a matter of evidence. Deciding what’s likely ahead of time limits the possibilities. It’s worth putting ideas out there and letting the data be the judge.”

Today, researchers from Australian National University, Swinburne University of Technology, and the ARC Centre of Excellence for All-sky Astrophysics (CAASTRO) made an announcement: They have detected three FRBs using the Molonglo radio telescope, near Canberra.

The research, led by Manisha Caleb, a PhD candidate, has confirmed that the mystery bursts of radio waves that astronomers have hunted for ten years really do come from outer space.

In 2013, scientists realized that the Molonglo telescope’s unique architecture could be used to pinpoint FRBs because of its enormous focal length. The telescope has a huge collecting area (18,000 square meters) and a large field of view (eight square degrees on the sky), which makes it excellent for watching for fast radio bursts.

“Conventional single dish radio telescopes have difficulty establishing that transmissions originate beyond the Earth’s atmosphere,” said Dr. Chris Flynn from the Swinburne University of Technology.

Caleb’s project was to develop software to sift through the 1000 TB of data produced each day. Her work paid off with the three new FRB discoveries. All three originated in outer space, and one was isolated to an individual galaxy.

Of her discovery, Caleb said,

“Figuring out where the bursts come from is the key to understanding what makes them. Only one burst has been linked to a specific galaxy. We expect Molonglo will do this for many more bursts.”

A paper on the discovery The first interferometric detections of Fast Radio Bursts has been accepted for publication in Monthly Notices of the Royal Astronomical Society.