Super-advanced civilisations could be plucking stars from other galaxies because the universe is expanding, theoretical astrophysicist Dan Hooper has said.
In 100 billion years, each part of the universe will become marooned – like a cosmic island – with resources from the rest of the universe inaccessible.
Theoretical astrophysicist Katie Mack of North Carolina State University in Raleigh said: “We’ll be in this very dark, lonely place where we won’t be able to see other galaxies.”
That isolation is thanks to a mysterious “dark energy” that is causing the universe to expand faster and faster, reports ScienceNews.
Aliens could harness the energy of stars by surrounding them with giant, hypothetical structures called Dyson spheres, before they disappear.
Aliens that possess such technology might want to maximise energy reserves by sending spaceships to retrieve stars before the cosmic isolation sets in.
However, the study doesn’t specify exactly how a civilisation might move a star, or what it would do with the energy once captured.
Theoretical astrophysicist Avi Loeb of Harvard University said rather than improving their home galaxy by collecting stars, aliens could simply jump to greener pastures.