“Space is big, really big,” says The Hitchhikers Guide to the Galaxy. Well, TIME is bigger. Humans exist for only an eyeblink in the cosmic tapestry, and in that time, all of our culture and civilization have arisen. It would disappear totally in a surprising short amount of time, measured in tens of thousands of years. Given 4 billion years of time, life’s history leaves room for multiple advanced civilizations to arise and die. Gavin Schmidt, climate modeler and director of the NASA Goddard Institute for Space Studies recently contacted University of Rochester astrophysicist Adam Frank and they explored two questions which yielded a very interesting paper:
“How do you know we’re the only time there’s been a civilization on our own planet?”
“Could we even tell if there had been an industrial civilization [long before this one]?”
Their exploration nods to Dr. Who with its title of “The Silurian Hypothesis: Would it be possible to detect an industrial civilization in the geological record?” You can read a much more approachable article by Steven Ashley at Scientific American.
“I find it amazing that no one had worked all this out before, and I’m really glad that somebody has taken a closer look at it,” says Pennsylvania State University astronomer Jason Wright, who last year published “a fluffy little paper” exploring the counterintuitive notion that the best place to find evidence of any of Earth’s putative prehuman civilizations may well be off-world. If, for instance, dinosaurs built interplanetary rockets, presumably some remnants of that activity might remain preserved in stable orbits or on the surfaces of more geologically inert celestial bodies such as the moon.
“Look, 200 years ago the question of whether there might be a civilization on Mars was a legitimate one,” Wright says. “But once the pictures came out from interplanetary probes, that was settled for good. And that view became ingrained, so now it’s not a valid topic for scientific inquiry; it’s considered ridiculous. But no one’s ever put the actual scientific limits on it—on what may have happened a long time ago.”
So what would the be? Not extraterrestrials certainly. Paleoterrestrials maybe? What do you think? Check it out.