Dr. David Bowman, orbiting Jupiter, is preparing to leave his spaceship. By this point in “2001: A Space Odyssey,” the onboard computer, HAL 9000, has murdered his fellow astronauts with the kind of unsmiling single-mindedness we’ve come to expect of artificial intelligence. Bowman slips his sweating forehead into the dome of a helmet and switches the wretched computer off, then opens the ship’s bay door to meet an entirely different category of intelligence on the other side. Contentedly orbiting Jupiter is the alien Monolith, with its perfectly straight surfaces, its inert intelligence boiling under glassy black panels.
No, this is not the kind of extraterrestrial life our imaginations yearn for. Where are the little green men, we ask, with their tentacles and their eyes, with their flying saucers and their warp drives? But according to a new collection of essays written by some of the world’s preeminent cosmologists, astrophysicists and geneticists, assembled and edited by Jim Al-Khalili, Clarke and Kubrick’s 1968 science-fiction film might be more correct than any of our popular imaginings; the gleaming monolith, a foreign and nonbiological intelligence, might be the best we can hope for. The authors of “Aliens: The World’s Leading Scientists on the Search for Extraterrestrial Life” ask the question “Where is everybody?” and come back with predictably scattershot answers.
It’s a question humanity has tried answering before. In 1870, the British astronomer Richard Proctor looked up at Venus, with its thick atmosphere, and nodded. Yes, he said, it’s definitely got life: Probably at the poles. We used to believe there was life on Mars too, huddled around the imaginary canali so confidently etched onto Italian astronomer Giovanni Schiaparelli’s 1877 map of Mars. Well, we know how both of those assumptions turned out.
Astro-geniuses of one day are recast as drooling schizophrenics in the next, firmly planted in pitiable ignorance. There’s a Bob Dylan line about this kind of thing; “Inside the museums, infinity goes up on trial.” Well, if you visit a science museum, you’ll see the guilty verdicts as read: Aristotle, Ptolemy, Proctor, Schiaparelli. All wrong in their own way, all laughed at by the next whiz kid. As we learn more about the universe, it pushes back, getting stranger, sneering at more PhDs. “This is the position of the universe with regard to human life,” Martin Amis writes in his novel, “The Information.” “The history of increasing Humiliation, dear sirs, proceeds apace.”
So what are the scientists doing now to answer the question? The SETI program is still chugging away, scanning the skies for the faint blip of a radio wave, a surefire sign of intelligent life. We haven’t heard anything yet.
According to Matthew Cobb, an evolutionary zoologist, this is because there are no alien civilizations. We’re truly alone—or we’re only accompanied by unintelligent prokaryotes, quietly stinking up some far-away rock.
“We can be beguiled by our unique abilities, and indeed by the very fact of our existence, into imagining that our evolution was the expression of evolutionary trends toward increased intelligence, and that given the immensity of space, these tendencies will be repeated on other worlds,” Cobb writes. “None of this is true. There is no direction to evolution … Even if we accept that abiogenesis [the creation of living matter from non-living components] is a relatively trivial event, that would almost certainly mean that we live in a Universe of slime, populated at best by unicellular biofilms aggregating on the surfaces of exoplanets.”
The other possibility, insists cosmologist Martin Rees, is that other intelligent life has already evolved beyond its organic sheathing into a non-biological intelligence that we couldn’t comprehend if we tried, like the Monolith in “2001.” How would we communicate with that? What would it think about soft-bodied things like us?
“Life on a planet around a star older than the Sun could have had a head start of a billion years or more … It may be only one or two more centuries before humans are overtaken or transcended by inorganic intelligence, which will then persist, continuing to evolve, for billions of years,” Rees writes. “This suggests that if we were to detect ET, it would be far more likely to be inorganic: we would be most unlikely to ‘catch’ alien intelligence in the brief sliver of time when it was still in organic form.”
Both outcomes are rather distressing. After hearing this, what are we supposed to do with science-fiction novels, movies and comics? Science-fiction aliens, with their damp grey skin and their slanting nostrils, with their fizzing intellects and their mind-bending spaceships, just won’t elicit the same shuddering gasps of “what if?” anymore. Books by Asimov or Card, Herbert or Wells will be met with a condescending smirk as the wised-up 21st century reader tosses the yellowed paperback aside for more realistic fare. Surely we would have heard from the likes of them by now, s/he’ll say. With a soft thud, the earnest science-fiction writers join the aforementioned astronomers in defeat.
A few of the book’s essayists hold out hope. Here’s the astrophysicist Sara Seager: “I must confess that I allow myself to speculate and daydream, because I am part of the first generation who has it within our reach to find signs of microbial life.” With a technique she helped develop, scientists plan to use high-powered telescopes to detect the biosignatures of exoplanets—compounds like Earth’s oxygen, which normally reacts with other compounds, but makes up 20 percent of our planet’s atmosphere because of continuous photosynthesis. Within our lifetime, the data will start rolling in.
Louisa Preston even remains optimistic about life on moons in our own solar system. Sure, a 62-mile-thick sheet of ice covers Europa, and liquid bodies of methane and ethane slosh on Titan’s frigid surface—but you never know.
For now, we’ll just have to speculate. Martin Amis once again puts it best, this time from his novel, “The Pregnant Widow”: “We don’t understand the stars, we don’t understand the galaxy. The night is more intelligent than we are—many Einsteins more intelligent.” Amis’ character, planted on a park bench, proceeds to “[sit] on, under the intelligence of the night.” If the scientists assembled in “Aliens” are to be trusted, then that’s all we can do—sit down, look up at the stars and revel in how little we know.
