Gigantic 'alien megastructures' built by an advanced civilisation could be orbiting dozens of nearby stars, boffin says


The world was electrified last year when it was suggested that scientists had spotted an “alien megastructure” orbiting a distant star.

Now a space boffin has suggested huge extraterrestrial constructions could be relatively easy to spot, so long as we look in the right place using the correct tools.

In 2016, one expert suggested the unexplained “winking” behaviour of a far-off sun called Tabby’s Star may have been caused by the rotation of a gigantic craft called a Dyson’s Sphere. 

These theoretical “megastructures” were dreamed up in the 1960s, when Freeman Dyson and Nikolai Kardashev suggested an advanced civilisation would inevitably seek to build a huge structure around a star to harvest its massive power.

Now an astronomer called Zaza Osmanov from the Free University of Tbilisi, Georgia, has suggested these gigantic solar power plants might be relatively easy to spot using current technology.

In a previous paper, he said the huge space stations are more likely to be shaped like thin discs rather than massive “spherical shells” which entirely surround a star.

This would allow a Dyson’s Sphere to exists in its parent star’s “habitable zone” – an area of space where life could thrive.

If some advanced alien empire really had built a ring in a star system’s habitable zone, it would be be heated to a temperature that it visible to current infrared telescopes such as the Very Large Telescope in the Atacama Desert of northern Chile, Osmanov,a new paper published on online archive Arxiv explained.

Osmanov called for the search for alien megastructures to focus on 64 pulsar stars which are relatively close to Earth.

However, he said it would extremely difficult to build a “cosmic megastructure”

“Rapidly rotating pulsars are very powerful and harvesting their energy would be quite profitable, but a habitable zone would be much farther and mass of a material required for constructing the mega-ring would exceed the total mass of all planets, asteroids, comets, centaurs and interplanetary dust in a typical planetary system by several orders of magnitude.”

So if an alien civilisation is powerful enough to build a Dyson’s Sphere, it’s probably strong enough to wipe out humanity.

Luckily, we haven’t actually got evidence that unequivocally proves the existence of any alien megastructure, so we can stop worrying about an imminent alien invasion for the timebeing.

This story originally appeared in The Sun.