Aliens are all the rage at the box office this year, appearing in sci-fi thrillers such as "Super 8," the comedy "Paul" and action movies including "Cowboys and Aliens," just to name a few.
For movie studios, extraterrestrials are a good bet: Ever since the advent of the motion picture, filmgoers have reliably forked over dollars to see them. Yet for escapist entertainment's sake, these on-screen aliens tend to be grotesque, mucosal monsters or kid-friendly, big-eyed charmers rather than beings plausibly from another planet.
Some movies, however, have at least nodded in science and history's direction, and in so doing have presented slightly more believable versions of E.T.
Arms and legs, or tentacles?
In an awful lot of movies, aliens look remarkably like us. This arrangement is convenient for narrative purposes, such as audience sympathy, and not to mention budgetary concerns (2009's "Avatar" for the former, and 1951's "The Day the Earth Stood Still" for the latter).
To a certain extent, it's anyone's guess as to what an alien might look like, because after all, we have yet to find anything living outside of our planet's biosphere. So it's certainly possible that intelligent, spacefaring aliens could stand erect on two legs, wave two arms and look upon us with two forward-facing eyes.
"You can't argue that something that looks like us is an implausible design for an intelligent species because obviously it works," said Seth Shostak, senior astronomer at the Search for Extraterrestrial Intelligence (SETI) Institute in Mountain View, Calif.
Accordingly, movies featuring humanoid aliens should not be deemed unbelievable offhand. But the anthropomorphic bias that directors sometimes have for their aliens' physical form is less a matter of scientific uncertainty than an unsubtle manipulation of audience expectations.
"Friendly (aliens) always look like children, while unfriendly ones look like arthropods or something you would order at a seafood restaurant," Shostak said.
Grudgingly, Shostak and other scientists interviewed for this article allowed that the 1977 film "Close Encounters of the Third Kind" is not as bad as most other alien flicks in the credibility department (though perhaps only by a sliver).
The aliens in "Close Encounters" — ultimately benevolent, as reinforced by the fact that many of them look like hairless children — do not win believability points for their appearance. Rather, it is historical context that makes them feel more "real."
In crafting the film, director and writer Steven Spielberg tipped his hat to many iconic cases in "ufology," the study of unidentified flying objects (UFOs) and their alleged extraterrestrial occupants' meddling on Earth.
Claimed abductions are one well-known example. So are "lights in the sky" at night on rural roads. Fittingly, in "Close Encounters," a Midwestern everyman's pickup truck is spotlit from above by a hovering alien ship. All sorts of electromagnetic oddities ensue: a flashlight goes dark, a metal railroad sign shakes as if buffeted by shifting magnetic fields and the truck driver gets sunburned on his face.
These phenomena jibe with accounts from UFO witnesses, said Bruce Maccabee, a well-known ufologist, retired optical physicist and author of the "UFO/FBI Connection: The Secret History of the Government's Cover-Up" (Llewellyn Publications, 2000), among other books.
"Spielberg knew his ufology," said Maccabee. (Indeed, the title of " Close Encounters of the Third Kind " comes from a ufological classification system.)
Not motiveless enemies
Although their overall intent is never explained, at least the aliens in "Close Encounters" were not illogically hell-bent on crossing vast cosmic distances only to wipe out humanity or invade our bodies, scientists noted.
Along these lines, another movie drawing mild plaudits for believability is 2009's "District 9." The shrimplike, bipedal aliens — known derogatorily as "prawns" — have families and experience emotional states like our own.
That intellectual congruity allows the aliens to be used symbolically as stand-ins for minorities, offering a new window on how societies mistreat them, said Sidney Perkowitz, a physicist at Emory University in Atlanta, and author of "Hollywood Science: Movies, Science, and the End of the World" (Columbia University Press, 2007).
"('District 9') brings in a different aspect of aliens (to film)," Perkowitz said.
Far beyond us
Another oft-pointed-to movie that does better by aliens than most is 1997's "Contact," which starred Jodie Foster as Ellie Arroway, a SETI scientist.
"'Contact' was wild, but not out of-the-question wild," said Carolyn Porco, the imaging team leader for NASA's Cassini mission, who helped advise on the movie as well as the 2009 remake of "Star Trek."
In the film, a decoded signal from space contains blueprints for a fantastic machine with three spinning rings; a capsule containing Arroway drops into the machine, hurling her through multiple wormholes; she eventually arrives at a metaphysical representation of a Florida beach, where — of all entities — her deceased father materializes.
The aliens behind this illusion, Arroway guesses correctly, have "downloaded" her memories and constructed a simulation in order to more easily communicate with her.
"'Contact' really handles things smartly by not showing the aliens, just showing us how advanced their technology is," Perkowitz said.
SETI's Shostak also liked that the aliens in "Contact" are immeasurably beyond us technologically. Our civilization is a mere 10,000 years old; extraterrestrial civilizations that emerged earlier in the universe could have had billions of years to develop incredible capabilities.
In movies, aliens are "usually just at the right level for us to take them on," Shostak said. "If you think of the timescales of things happening in the cosmos, that's completely bonkers."
Waiting to believe
At any rate, filmmakers of alien movies do not list "fidelity to science" as a chief aim of their productions that are meant to entertain well before they educate.
"Hollywood people don't see it as their duty to respect science — it takes a backseat," said Porco.
"To think (Hollywood is) informing you about the likelihood of what E.T. might be like is like thinking that John Wayne movies are good cultural insights into the American Indian," joked Shostak.
Of course, aliens were not considered a topic worthy of study in the scientific community until relatively recently, so a dearth of "realism" in the multiplex seems to be a foregone conclusion.
But the surge of exoplanet discoveries since the mid-1990s, along with the expected confirmation of a habitable, Earthlike planet almost any day now, is changing attitudes. Aliens gaining traction in academia could pave the way for somewhat believable versions of them to grace the silver screen someday.
"Not too long ago, if scientists (at a conference) had had a session on alien life, they would have been laughed off stage — now it's taken pretty seriously," said Perkowitz.
"In the next few years, maybe we'll see some scientists worry about this (cinematic credibility gap)," Perkowitz added, "and those scientists will be consultants on movies."