Astrophysicist: Ancient Life in Our Solar System Not Ruled Out

The possibility a long-gone, technologically advanced civilization once flourished somewhere in our solar system has never been ruled out – and its traces are just waiting to be discovered, a provocative new paper argues.

Penn State astrophysicist Jason Wright, writing the paper "Prior Indigenous Technological Species," which was posted on the online research archive ArXiv, says if a technological species existed in our solar system, it might have originated on Earth, or a "pre-greenhouse" Venus, or on Mars when it still had flowing water, NBC News reported.

And it might have left behind "technosignatures" – a range of possible artifacts that include archaeological ruins and old mining operations as well as synthetic chemicals or nuclear isotopes that could have been created only by technological processes, Wright contended.

The hunt should focus on Mars, where they could be lying deep under the surface, the Earth's moon, and the rocky moons and asteroids of the outer solar system – or even in "large structures free-floating in space" that were left over from the hypothetical civilization, Wright argues.

"I'd like people who think about ancient Earth — archaeologists and paleontologists — to consider how we can rule out a prior indigenous technological species," Wright told NBC News. 

"Before what [geologic] time are we sure that there was no complex life, no technology, on the surface of the Earth? I feel that planetary scientists can tell us how old the surfaces of Venus and Mars are, and how long artifacts should last."

So far, his theory has gotten a tepid response from space scientists.

"If I had to guess, I'd say it's highly unlikely, but not impossible, that an ancient civilization existed — probably even more unlikely we'll ever find evidence," Paul Horowitz, a research professor of physics and electrical engineering at Harvard University and a noted expert on the search for extraterrestrial intelligence, told NBC News.

Neil deGrasse Tyson called Wright's ideas "intriguing," but added efforts to confirm the existence of another home-grown technological species would "require substantial upticks in our space exploration budgets," NBC News reported.

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