One of the first things I learned in producing this episode is that most everyone involved in planetary science these days is thinking about alien life. It’s the hot topic among space scientists and it’s indicative of just how much has changed in the science of looking up at the stars.
It wasn’t so long ago that if you were a scientist and wanted to be taken seriously – and all scientists want to be taken seriously – you didn’t talk about life in the universe. Look what happened to Carl Sagan. Back in the 70s he went public with his views on aliens and many think that’s what cost him his membership in the National Academy of Sciences. Back 15 years ago, to be safe you didn’t even tell colleagues you were a sci-fi buff, even though pretty much everyone was. But the climate has changed and scientists now have business cards that read “Astrobiologist” and work in departments with the word “Exobiology” in the name.
We owe this shift to UC Berkeley astronomer Geoff Marcy, who gambled his career on a wacky idea… to find planets orbiting other stars. Geoff told me that back in the early 90s he figured his science career was coming to an ignominious end, so he figured he’d take a chance and focus his research on finding planets orbiting other stars.
“I remember lingering in the shower one morning for half an hour and thinking to myself, okay apparently I’m not doing very well as a scientist. I should go for broke,” Geoff told me. “And it was then, with the water falling down on me in the shower, I realized I’m going to try to find other planets.”
And that’s just what Geoff did. He found planets… lots of planets. So many planets that he completely changed the way astronomers viewed the universe. Instead of planets being rare we now think they may be orbiting 20 percent of the stars in our galaxy. That’s 20 billion stars with planets.
The discovery of all these planets is what opened the doors and let all these scientists out of the closet to ask the question we all want to know… are we alone? So now we’re looking for small rocky planets like Earth orbiting stars at a distance where liquid water might exist. Scientists are busy preparing for another mission that would sample the atmospheres of those planets by analyzing the light filtering through them. If they find things like free oxygen or water vapor, there’s a good bet that something’s crawling around down there.
Video: Strange Aliens
It’s also reinvigorated the search for life elsewhere in our own solar system. Scientists think there’s a deep ocean of liquid water on Jupiter’s moon Europa. We know there’s liquid water on Saturn’s moon Enceladus and there’s lots of frozen water just under the surface of Mars. Might one of these worlds have life? Some scientists think we may have already seen signs of it.
On Mars something strange is going on. Every fall methane appears in the atmosphere. Methane is one of the by-products of decomposition. On Earth we get methane in our atmosphere every fall when leaves and bacteria die due to the cold. Some think the same thing’s happening on the Red Planet. In fact, NASA has gone out of its way to downplay the methane cloud/alien life scenario until they have proof. And that could come within the next 10 to 20 years.
There was a lot of new and exciting science to talk about in this episode and given the time constraints of television, there’s no way we could get into it all. But suffice it to say, some really smart people are looking into alien life and they all seem to think that within our lifetime we’ll know whether or not we’re alone in the universe.
Don’t miss the all-new episode of Known Universe, Alien Contact, tonight, Thursday April 15 at 10P et/pt!