Fast radio bursts may be a sign of alien civilisations according to Harvard researchers

Fast radio bursts (FRBs) are mysterious cosmic phenomena with no known scientific explanation. FRBs are radio bursts with too much energy to be completely explained by known high energy celestial objects such as black holes, neutron stars, magnetars, nubulae, supernovae or blitzars. Harvard researchers Manasvi Lingam and Abraham Loeb decided to investigate explanations for FRBs that involved artificial sources, as natural explanations were falling short.

Turns out that humans have already thought of the technology that could explain the FRBs. The breakthrough starshot is one of the earliest attempts at interstellar travel by mankind, and involves propelling a tiny spacecraft with solar sails using high energy beams of laser for propulsion. The lightsails of the spacecraft doubles up as the antenna. Such a craft could cover the distance to the closest stellar neighbour of the Sun, Alpha Centauri in as little as twenty years. By comparison, New Horizons, the fastest spacecraft ever built would take 80 years to cover the distance.

Now, what if you want to drive an interstellar colonial ship, with a weight of a million tons, about twenty times larger than the biggest cruise ship on Earth? You would need a massive device, twice the size of the Earth, cooled by water to prevent the underlying structures from being melted by the immense energies involved. The device would redirect the energy from a host star to a focused light beam to drive a spacecraft with solar sails. Such a device could adequately explain the pattern of FRBs, as seen from the Earth.

“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. An artificial origin is worth contemplating and checking,” said Loeb. When asked if he actually believes that the FRBs originate from colossal construction projects by advanced extraterrestrial life forms, Loeb 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.”

While the construction of such a device is beyond the scope of current human technology, there are no physical constrains that prevent such a device from being constructed by a more advanced civilisation. The resulting structure would be sufficient to transport living passengers not only between two stars, but between two galaxies as well. The repeated appearance of FRBs can provide further clues on the artificial origin of the signals. The observed characteristics of the FRBs are consistent with the assumption that the beams are artificial in origin.

The beam needs to be constantly focused on the spacecraft, and relative to the Earth, the spacecraft, the device, the host star and the galaxy it is in are all moving. This means that the beam sweeps across the sky and is only visible to humans on Earth for the briefest periods of time. Fewer than two dozen of these FRBs have been detected so far, and most have been traced to distant galaxies billions of light years away. The research has been presented in the Astrophysical Journal Letters and is available online .

In January this year, a team of researchers were among the first to pinpoint the location of an FRB . A fast radio burst was traced to originate from the constellation of Auriga. The light traveled three billion light years and the energy source must have been enormous to do so. The FRB is the brightest radio phenomenon known to man. The region of the sky is relatively busy, with a hundreds of stars, galaxies and other celestial objects. While the source is unknown, advanced alien civilizations are more likely to exist in busy portions of the sky.

KIC 8462852 is another mysterious light source that could potentially be a sign of an advanced extraterrestrial civilization. The star has a unique light signature very different from other stars, and can only be explained by a number of large objects in orbit around it. A debris field of colliding planets or a number of disintegrating comets are potential explanations, but these phenomena are relatively short lived in cosmic timelines, which makes it extremely unlikely that humans would have observed such a light signature. An alternative explanation is that the star is at the middle of a Dyson sphere, an object that harvests energy from the entire star. A Kickstarter project to investigate the star has been funded.

Recently, Nasa’s discovery of seven Earth sized exoplanets in orbit around an ultracool dwarf star, known as Trappist-1, about forty light years away, was another major step forward in the search for extraterrestrial life forms. Three of the planets are in the habitable zone of the host star, and with the right conditions, all seven planets may have liquid water on the surface, ideal conditions for life as we know it on Earth. Nasa’s James Webb Space telescope will investigate the Trappist-1 planets for signs of life, and the Canadian Chime telescope is meant to look for and identify more fast radio bursts.