The solar system that humanity calls home may have once been inhabited by an extinct species of spacefaring aliens, a top scientist has suggested.

A space scientist has suggested ancient extraterrestrials could have lived on Mars, Venus or even Earth before disappearing without a trace.

In a fascinating academic paper about “prior indigenous technological species,” Jason T. Wright from Pennsylvania State University raised the fascinating possibility that evidence of these extinct aliens could exist somewhere in the solar system.

Wright is an astronomer who received global attention after suggesting an “alien megastructure” had been spotted in orbit around a distant star.

Now the stargazer has said advanced aliens may have left behind “technosignatures” for us to find — if only we knew where to look for them.

“A prior indigenous technological species might have arisen on ancient Earth or another body, such as a pre-greenhouse Venus or a wet Mars,” he wrote.

However, most of the archaeological evidence of an ancient civilization would probably have been lost.

Earth’s plate tectonics would effectively have “erased” the traces of a civilization that lived billions of years ago.

Venus is in the grip of a severe greenhouse effect and also undergoes similar “resurfacing” that would scour it clean of artifacts.

This leaves just a handful of places where archaeologists might find traces of a lost extraterrestrial civilization.

“Remaining indigenous technosignatures might be expected to be extremely old, limiting the places they might still be found to beneath the surfaces of Mars and the moon, or in the outer solar system,” Wright added.

He said alien evidence was likely to be buried beneath the ground, allowing it to survive asteroid impacts.

“Structures buried beneath surfaces might survive and be discoverable as long as they do not suffer a collision so severe that their artificial nature is obliterated,” Wright added.

“Merely destroying them would render them nonfunctional, but they might still be recognizably technological.

“We might conjecture that settlements or bases on these objects would have been built beneath the surface for a variety of reasons, and so still be discoverable today.”

The astronomer suggested that very old spaceships could still be lingering in the Asteroid Belt or Kuiper Belt, a disc at the very edge of the solar system that’s made up of icy objects.

These artifacts are likely to be the remains of ancient probes, space bases or industrial facilities.

“In the case of a prior indigenous technological species, the artifacts might have had totally different purposes, such as asteroid mining operations or settlements on other planets and moons,” Wright wrote.

“Such structures would be expected to fall into disrepair, especially if its creators are absent.”

So where are these aliens likely to have come from?

Wright suggested they may hail from somewhere that’s very close to home.

The presence of intelligent life on Earth makes it more likely that ye olde aliens hailed from this solar system, rather than being descended from an “extraterrestrial species that crossed interstellar space,” he concluded.