Who Cares About Life on Other Planets?
Posted by Richard Conniff on August 13, 2012
Another misguided piece of NASA propaganda appears on the New York Times op-ed page today, arguing that we really need to pour billions more into outer space. I like exploration, which is why I wrote a book about it.
But here’s my argument for discovering and protecting what we have here on Earth first:
You may have noticed the welter of headlines lately about planets outside our solar system dubbed “earth-like” or “potentially habitable,” orbiting in what astronomers call “the Goldilocks zone.” That’s the elusive sweet spot close enough to a star to be not too hot and not too cold for life to begin. Most of the recent announcements about these “exo-planets” are a product of the Kepler Telescope, launched by NASA in 2009 and credited, at last count, with having identified 139 wannabe Earths.
The excitement among scientists is understandable. People have been wondering for centuries if there are planets like ours beyond this solar system. Or, as it’s often phrased: Are we alone in the universe?
Honestly, though, these stories mostly make me yearn for what the Book of Common Prayer calls “this fragile earth, our island home.” As with the mothers who raise us, we tend to take her for granted. Space exploration advocates have somehow persuaded us that it’s more exciting to look outward, and that finding any hint of life in outer space would be momentous, even down to the microbial level (also known as “exo-crud”). But even as NASA spends $50 million a year on astrobiology, plus $600 million so far on Kepler, we spend pennies to find the alien life forms we know live all around us here at home.
By conservative estimates, about 80 percent of species here on Earth remain undescribed. Even biologists discovering new primates do so on a NASA publicist’s lunch budget, though these are creatures more astonishing than anything we will ever see in outer space. We spend almost nothing even on identifying species that might keep us alive. And we act as if natural life forms are worthless unless proven otherwise. The Pacific yew tree, for instance, was widely considered a “trash” species—until it turned out to be the source of Taxol, a $1.7 billion-a-year drug that now routinely saves the lives of cancer victims.
The idea that finding intelligent life in outer space would somehow relieve our deep sense of being alone in the vastness of the universe also blithely overlooks the braininess all around us here on Earth—the way honeybees waggle-dance to map out the location of a flower patch for their hive mates, or the idea that a border collie named Chaser can recognize words for more than 1000 objects. This is how narrow-minded the exo-planet set can be about life here on Earth: According to a recent article in one scholarly journal, the real value of studying how species on Earth communicate is to “de-provincialize” our thinking about how to communicate with extraterrestrials. This makes my head explode.
Hyping exo-planets while dumping on the real Earth is like ignoring your attractive and intelligent wife, because somewhere in the universe Scarlett Johannson lives.
Though it’s not the fault of the Kepler scientists, the search for “habitable” planets is also tainted by the lunatic idea that humanity needs someplace to escape to when we reduce this planet to ashes. Physicist Stephen Hawking has argued for drastically increased spending to find a way off this planet; he figures a quarter of one percent of the world’s annual gross domestic product would be a good start. You might think it would be more practical to spend that money fixing big problems here on Earth like nuclear proliferation or climate change. But Hawking makes that sound like a holding action. “Our only chance of long-term survival is not to remain inward looking on planet Earth,” Hawking declared recently, “but to spread out into space.” One headline summed up his argument this way: “Abandon Earth or Face Extinction.”
Will the Kepler discoveries actually improve our chances of escape? That’s not the point of the program. But that’s what the public thinks when scientists chatter about “earth-like” or “potentially habitable” exo-planets. NASA, with its instinct for marketing (and perhaps also with an eye to extending the Kepler budget) surely knows it. Too much enthusiasm can, however, also hurt. After being featured on the front page of The New York Times, one early Goldilocks contender, Gliese 581-g, turned out to be little more than a smudge on the lens, a fairy tale. Other planets commonly get described as “potentially habitable” merely for being in the Goldilocks zone, though scientists lack basic details like whether there’s an atmosphere, how hot it gets, and even whether we are talking about setting foot on solid rock, or roiling gases.
Kepler 22-B is the celestial bolthole du jour, said to have a climate worthy of a shopping mall. An astronomer has predictably dubbed it “a phenomenal discovery in the course of human history.” But 22-b is also 600 light years away. In human history terms, getting there would take 100 times longer than Homo sapiens has existed as a species.
“We have no evidence that any planet is habitable,” says MIT astrophysicist Sara Seager, a member of the Kepler team who has tried to tone down the exo-planet hype, “and we won’t have that evidence for a very long time.”
Even if Earth were to become “a lot less habitable than it is now,” she says, it would still be far easier to construct a livable space in the desert or under the ocean than on another planet. It may be inspiring to think that “hundreds or a thousand years from now,” people may travel to other planetary systems. But it won’t be because they need to. “They’ll be traveling there in the interest of exploration.” Meanwhile, says Seager, “There is no Plan B.”
Abandon the Earth? Giving up on our island home isn’t an alternative to extinction.
It’s a recipe for it.