Here's What Aliens Actually Look Like, According to Scientists
The biggest problem with imagining what aliens will look like is the fact that all we know is the Earth. We've seen life develop in millions of way, from seals to lizards to jellyfish, but what if the Earth was much, much colder? What if life never left the oceans? It's hard to imagine life going down a path we can't even imagine. Michael Crichton's bestselling book The Andromeda Strain pointed out that humans have another bias when visualizing aliens: they usually end up looking like us.
It's no surprise that most of our private images of aliens come from films like E.T., Alien, and Close Encounters of the Third Kind—these films evoke emotional reaction from audiences, whether it's affection, fear, or otherworldly awe, and that's a powerful way to ingrain an image in someone's head. For better or worse, there's a trick to making effective on-screen aliens—according to Charley Henley, a VFX supervisor who's worked on several of the Alien films, "A lot of [Ridley Scott's] designs are tied in with the human anatomy, and I think that is the common theme. We put a lot of humans into the aliens."
Henley notes that sci-fi filmmakers and designers actually run into trouble when they try to create aliens that aren't based on Earth life. He cites the Mimics in Edge of Tomorrow as one example of an alien creature whose brief called for a design that was completely...well, alien. It wasn't supposed to be based on Earth life, and instead looks like a writhing mass of worms. "The challenge with anything like that is that if it doesn't follow laws that we know...it's hard to sell it as something that's real and tangible."
So we're caught in a trap: we can't believe any portrayal of aliens that isn't somehow based on the life that we know, but there's almost nothing that guarantees alien life will follow the rules we're familiar with.
However, Michio Kaku has at least three guesses based on his interviews with exobiologists: 1) they'll most likely have stereoscopic vision (due to their evolution from predator ancestors), 2) they'll have gripping appendages or thumbs to create tools, and they'll most likely have language, and 3) it's also likely that they'll evolve on icy moons similar to Europa, meaning that they'll probably be aquatic. In fact, Kaku says that they'll probably look like octopuses.
If that's the case, then H.P. Lovecraft really was ahead of his time.
Of course, there's another argument that's just as likely considering our conceptions of what aliens actually look like are at best just educated guesses: aliens look exactly like they've been portrayed in pop culture.
According to director of SETI Research Center at UC Berkely Andre Siemion, it's entirely possible that Hollywood has actually gotten aliens right all along.
"It's science fiction. I mean, as of now, hopefully, someday we will detect life on another world—maybe many examples of life on many worlds—and then we can have more accurate science fiction. But I think as of now, a guess of a science fiction novelist is as good as a scientist," Siemion said. "Science fiction is one expression of our profound sense of awe and wonder about whether we are alone in the universe."