There may not be life on Mars, but there could be on ten billion trillion other planets
What’s more, we’ll probably discover the first evidence of extraterrestrial life within decades, claims astrophysicist Adam Frank, author of a new book on aliens, who believes so-called ‘Goldilocks worlds’ containing water already exist
NEXT time you’re staring up at the night sky, consider this: there are around ten billion trillion planets in our universe that could support alien life. That’s the conclusion of astrophysicist Adam Frank, a NASAfunded scientist who has dedicated his career to searching for intelligent extraterrestrial life. “I can say with great confidence that pretty much every star in the sky hosts a family of worlds,” he says.
“And that one in five of them hosts a planet in the right place for life to form. That’s a lot of Klingons, Wookiees and Predators.” Chewbacca aside – the longhaired best friend of Han Solo in Star Wars is the only nice alien on that list, after all – it’s a perturbing thought.
So far, using powerful telescopes, astronomers have laid eyes on around 5,000 planets outside of our own solar system, also known as exoplanets. They do it by detecting tiny reductions in light as the planets pass in front of their distant stars.
But astronomers are certain that virtually every star in the universe has multiple planets spinning around it – and that one in five stars has a planet at just the right distance for liquid water to exist on the surface.
Liquid water, of course, allows life to form. Astronomers call these Goldilocks planets.
“It’s hard not to have your mind blown by the numbers,” Adam writes in his latest book, The Little Book of Aliens. “Just a few decades ago, no one knew if even one stinking exoplanet was out there in orbit around a single other stinking star.
“Now we can say with confidence that there are roughly ten billion trillion planets
‘If we find one more example of life, it means there are lots of examples and life is everywhere’
in the right place for life to form. The sky is rich in worlds.The galaxy is rich in worlds.
“The universe is rich in worlds. A universe of worlds means there are probably many where snow is falling in silent canyons, winds are blowing through mountain passes and waves are breaking on golden beaches.”
Adam, 61, has been obsessed with aliens since childhood when he first read his father’s science fiction magazines. He admits he was an annoying and precocious kid – his favourite trick was to quote the speed of light to four decimal places.
But his obsession drove him to watch every space documentary, sci-fi film and TV series he came across.
In fact, as he talks to the Daily Express from his home in Rochester, in upstate New York, the digital backdrop to his video call is the bridge of the Starship Enterprise from Star Trek. It’s fair to call Frank an alien geek.
And now a professor of astrophysics at the University of Rochester, this geek is currently funded by NASA to search the heavens for signs of alien civilisations.
There’s just one problem: the heavens are endlessly vast, telescopes can only point in one direction and few astronomers like Adam are actively searching for life. “Imagine the night sky is the ocean, and you’re looking for fish,” he explains. “Then, in the entire world’s oceans, we’ve only looked at a hot tub’s worth of water.”
In his book, Adam addresses some very profound cosmological ideas.
There’s the Fermi paradox, for example: if advanced alien life has developed elsewhere in our galaxy, why have aliens not landed on our planet and announced themselves to us?
Why aren’t there aliens among us right now,Adam asks, “chatting us up on the street or taking over the Government”? Then there’s the Drake equation, an estimate by 1960s astrophysicist Frank Drake, who calculated that, just within our own galaxy, The Milky Way, there are up to 100 million planets with advanced civilisations.
As for Dyson spheres, the idea that vast solar panels might be built around distant suns by advanced alien engineers, Adam has a theory. He believes wormholes – hypothetical tunnels between different regions and time periods in the universe, first proposed in Albert Einstein’s general theory of relativity – might exist.
And he cites cryosleep as essential should we become a spacefaring species in the future. The process of freezing astronauts’ bodies so that they can travel for light years across the galaxy without ageing was until recently considered pure science fiction, featured in films from Kubrick’s 2001: A Space Odyssey to Ridley Scott’s Alien. Without it,
and relying on current technology, Adam says it would take our most advanced spaceships 80,000 years to reach even the closest star to our own Sun, Proxima Centauri.
He also seriously suggests very basic alien life may well exist in our own solar system, on some of the ocean moons orbiting Saturn, Jupiter and Neptune.
“We absolutely have to consider the possibility there’s at least microbial life,” he says. “Why not? You’ve got water, you’ve got geothermal vents, and you’ve got the chemicals. So you have a lot of the things you need for life to form.”
Adam cites two of Saturn’s moons, Titan and Enceladus, and one of Jupiter’s moons, Europa, as the most likely contenders.
But, in the grand scheme of things, microbial life is rather dull. Far more intriguing are the astrophysicist’s plans to use telescopes to identify advanced civilisations on planets in far off solar systems.
By analysing the starlight that passes through a distant planet’s atmosphere – a process known as spectroscopy – he hopes to spot signs of pollution, or city lights, or orbiting satellites, or the reflection from vast solar panels, for example.
“Sitting here on Earth, an astronomer can figure out exactly what’s in a planet’s atmosphere even if that planet is tens, hundreds, or thousands of light years away,” he explains.
Despite being convinced that far off alien civilisations exist, he is dismissive of the idea that little green men regularly visit Earth.
He says the world’s growing obsession with UFOs – or UAPs (unidentified aerial phenomena) as they are known nowadays – all began in June 1947 when amateur pilot
Kenneth Arnold was flying his single-engine plane near Mount Rainier, in the north-west US. Suddenly Arnold spotted flashing lights from nine objects flying unfeasibly fast in a diagonal formation.
After he had shared his story with friends, reporters from a local newspaper interviewed him and he described the nine objects as moving like “a saucer if you skip it across the water”. An over-excited journalist then wrote up the story, using the misquoted words “saucer-like aircraft”.
VERY quickly, the story, and the misquote at its heart, gathered pace. One of America’s largest newspapers, the Chicago Sun, published an article with the headline “Supersonic Flying Saucers Sighted by Idaho Pilot”.
Adam explains: “Within six months, the flying saucer story ran in over 140 newspapers throughout the US. Even more remarkable, an epidemic of flying saucer sightings began to sweep the nation.
“In the months following the story, more than 830 UFOs were seen in the US and Canada, most of them being described, interestingly, as saucer-shaped. By the end of summer 1947, ‘flying saucers’ were officially a thing.”
Adam distances himself from this “funhouse mirror world of UFOs,” and “tornado of the absurd”, preferring to concentrate on his search of distant planets instead.
He’s hopeful that, by 2040, NASA will launch its next generation of space telescope, known as the Habitable Worlds Observatory. As NASA explains: “HWO would be designed specifically to identify potentially habitable planets around other stars, closely examining their atmospheres to determine if life could possibly exist.”
But how would finding evidence of distant life forms be of any benefit to humankind? Given the vast distances involved, sceptics would consider it a fruitless task.
“I would argue it will be one of the most significant developments in human history,” Adam insists. “Finding out that humans are not an accident; finding that we’re not alone, even if it’s dumb life; finding that we’re not the only time in cosmic history where this wild, innovative, insane thing called life occurred would completely transform our philosophies and religions.
“We would now understand we’re part of a cosmic community of life. If we find one more example of life, then it means there are lots of examples, and life is everywhere.Who knows what the possibilities are? It means there really is no limit to life. From microbes to us.What else has happened?”
Adam is optimistic he and his colleagues will find evidence of alien life within his lifetime.
“I’d take any form of life; it doesn’t have to be intelligent,” he says. “Microbial life would be just as important and just as mind-blowing as finding giant aliens.
“My most profound hope is that I see that, before I pass into the great beyond. I think we are living in the first generation that will get some kind of answer.”
● The Little Book of Aliens by Adam Frank is out now