Last night’s Stargazing Live revealed four newly-discovered planets orbiting a distant star. Discoveries like this are hugely exciting because they hold out the tantalising prospect of planets harbouring alien life.
But if we ever do encounter aliens, what will they be like? Have we been well prepared, or led down an intergalactic garden path, by all the little green men that litter the history of cinema?
The two co-hosts of ABC podcast Cosmic Vertigo, Dr Amanda Bauer and Dr Alan Duffy, are astronomers but also sci-fi fans. In the latest episode, they discuss the search for alien life.
So we asked them, as scientists: What is your all-time favourite movie alien?
Amanda: E.T. Full stop.
Alan: Oh, come on! Really?
Amanda: Look, I think a test of a good sci-fi film is how well it ages, and while I’m slightly hesitant to admit this — I watched E.T. recently and cried. And laughed. And got goosebumps all the way through and felt nostalgic for all those times I watched it as a kid. Sure, it’s far-fetched that an alien species would look so similar to humans and be so incredibly cute… It’s just a great movie!
And then there’s WALL-E, who looks oddly similar to E.T. now I think about it. Maybe I just like the friendly ones, instead of all those aliens who visit Earth only to have humans jump to evil conclusions and inevitable misunderstandings and then OMG THEY’RE GOING TO DESTROY US, WE MUST DESTROY THEM FIRST.
Alan: WALL-E is not even an alien.
The one and only WALL-E
Amanda: I guess you’re right. Fine! I’m clearly not the sci-fi expert you are…
Alan: I’m definitely a fan. And I think it’s an incredible way to present great science to many millions of people. There are wonderful examples of films getting the science right.
Take Gravity, Interstellar and 2001: A Space Odyssey. They didn’t get absolutely everything right, but some of their most accurate scenes are also some of the most engaging. Wonderful cinematic moments and wonderful scientific demonstrations at the same time.
Like all the micro-gravity scenes in Gravity — full of the tension of just being out of reach, powerless to propel yourself forward without being able to interact with another object. This is beautifully realised Newtonian dynamics! And in a setting that not even Isaac Newton could have imagined.
Amanda: Wait, am I allowed to talk about where Gravity got it WRONG now? They rendered the Hubble Space Telescope and the Soyuz Spacecraft beautifully — but the chance of the astronauts cruising between the two spacecraft, whose orbits above Earth differ by 140 kilometres in height, with nothing but jet-pack propulsion, and then just grabbing on?! Nope. Not possible.
Alan: OK then, let’s talk Interstellar. The modelling they used to depict that black hole was so involved that a new effect was noticed: the halo-like warping of the glowing accretion disk around the black hole. It was written up in a scientific journal by the movie’s science advisor Professor Kip Thorne!
Amanda: Yeah, that was cool. My first university summer research project started by reading Kip Thorne’s Black Holes and Time Warps: Einstein’s Outrageous Legacy. The book started with a short sci-fi story about what you would experience if you flew your spacecraft near a small black hole versus a supermassive black hole, and then continued by explaining all the physics and general relativity that lead to why we think those things actually exist. It was awesome.
Alan: And what about the ultimate masterpiece? 2001: A Space Odyssey. The rotating spacecraft that mimics Earth-like gravity because of its centripetal acceleration, or the wondrous silence punctuated by moments where air pressure (and hence sound) return; they all add to the film, while faithfully exploring scientific concepts in front of a huge audience.
Amanda: Love the music, love the ideas… But this film also creeped me out about artificial intelligence in a way that I’m still not completely comfortable with!
Anyway — let’s get this back to aliens. If you’re such an expert, what’s YOUR favourite move alien?
Alan: That’s tricky. Space is sometimes explored really well in the movies, but the fictional aliens that live there are usually much less convincing.
The common plot line, where aliens are so advanced as to travel hundreds of trillions of kilometres between the stars and then invade us, is just bizarre! Why harvest the resources on Earth when there is so much more available — and already in bite-sized chunks — lying in the asteroid belt?
Amanda: True. And you guys, in your enormous ships, flew right past all those asteroids to get here!
Alan: I’m looking at you, Independence Day. Don’t get me wrong, I loved it! Just not for the science. And it’s a shame they never made a sequel. EVER. Independence Day 2 never happened.
Amanda: Even if they did decide to come and fill their alien bellies on Earth — would it do them any good? And why is it always us, and not any of rest of the life on Earth? Why do they never start with some nice fruit or vegetables?
Alan: That’s true. The idea that the aliens can somehow use our bodies is incredibly unlikely.
Considering that we share most of our DNA with life on Earth, and yet are violently sick (at best) if we try to eat almost any of it — then how would an alien from space, which shares none of that DNA, possibly be able to eat us? Let alone, as in Aliens, go one step further and use us as a host, or even somehow take DNA characteristics from that host! Remember the dog-alien?
Amanda: But there are some great movies about aliens. Like the ones where we don’t actually meet each other! After all, the distances are so vast that our bodies probably won’t make the trip.
Alan: Unless Interstellar is right and wormholes exist! And, sure, they’re technically allowed by physics, just… highly suspect.
Amanda: But instead of meeting face-to-face, maybe we will communicate. Like in Contact — I love that movie. It’s a wonderful description of the way we might uncover such a signal, and it’s a great exploration of the range of responses from the public too.
Contact came out when I first started studying physics and I constantly got told, “You remind me of that lady in the movie with the headsets…” Jodie Foster? “YES!”
But by the time I started teaching, the students were too young to have seen that movie. Sad.
Alan: Just last year we had an update on that style of movie — Arrival, which I completely loved. It has a strong female lead scientist, and a great depiction of how diverse communication can be. Also it shows how challenging it will be to recognise it, if we do hear anything with our radio telescopes!
And we are certainly listening. Telescopes around the world, including the Parkes radio telescope in Australia, are looking for just this sort of signal as part of the Breakthrough Listen project. The science is finally catching up with the science fiction.
Amanda: Maybe our search for life in the universe, in reality and in the movies, is more about understanding what makes it possible here on Earth — and gaining insight into ourselves.
Alan: Totally. When we explore space and contact aliens in film, what we’re really projecting onto the big screen is us.