I love this idea of a creature being defined by astrophysics. After all, we are too! We see in the part of the spectrum that our Sun radiates most of its energy, we sleep when it is night because of the Earth’s rotation, we breathe oxygen, and our bodies are adapted to Earth’s gravity.
Sadly, later analysis showed that 40 Eridani Ab is probably not a real planet after all — the signal was likely due to activity on the star. But it is a great example of how an astronomical mistake can be responsible for the genesis of one of the greatest characters in science fiction history.
This has happened before! In 1877, Italian astronomer Giovanni Schiaparelli observed what he called canali on Mars, by which he meant channels. This was mistranslated as “canals.” Other astronomers took optical illusions as evidence of this, and in the late 19th and early 20th century, astronomer Percival Lowell started to popularize the idea that there was a race of Martians. This led to an explosion of science fiction and ideas that persist to this day in our culture.
Rocky Physiology
In all likelihood, aliens would look nothing like us because we are the result of untold trillions of choices that shaped us in natural selection. Just look at the millions of species on earth — not all have eyes, mouths, arms, legs, bones, or bilateral symmetry. And all Earth creatures were derived from a single common ancestor. Plus, we share an environment and a star that shaped our evolution. Imagine evolving with a different sun, different gravity, different atmosphere and pressure, different temperature, and a different length of day. The problem is, we empathize better with creatures who look like us, so there is a massive bias in science fiction towards humanoids.
Ryan Gosling stars as Ryland Grace in PROJECT HAIL MARY, from Amazon MGM Studios.
Photo credit: Jonathan Olley
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“Rocky is one of the first cases of a non-humanoid, truly alien main characters.”
Project Hail Mary shows that we can break out of this trope! Rocky is one of the first cases of a non-humanoid, truly alien main characters. Eridians are fascinating creatures — they don’t have eyes or a face. Though they are the size of a Labrador, they are really sturdy, and they’re made of rock. Their bodies are pentagonal, about 18 inches wide and 9 inches deep, with five legs. Eridians don’t breathe, so to make sound, they just move around air internally, as whales do. Ever notice that whales don’t make bubbles when they sing?
I love the idea of aliens communicating with music, like birds and whales. This has deep roots in physics, since musical notes are just vibrations on a string — it is something that could well be universal. We saw a similar concept in Close Encounters of the Third Kind, which is referenced in the movie.
I love the fact that Grace and Rocky had to take the time to sit down and learn each other’s languages, and we get to see some of the difficulty of trying to communicate with an alien species. We covered that in our Science Vs. Cinema episode on Arrival, so if you’re interested in that fascinating subject, we went deep, talking to linguists, SETI expert Seth Shostak, and even my dog Tater.
Echolocation
Eridians don’t need eyes because they live in total darkness. Their planet has such a dense atmosphere that light doesn’t reach the surface, much like the bottom of the ocean. There are creatures on Earth that have evolved to live in caves and have lost their eyes, like the Mexican tetra, a blind fish that finds its way by lateral lines — sensing organs that detect changes in water pressure. The Movile cave in Romania is also fascinating, because it’s been sealed off from the outside world for 5 and a half million years, where dozens of new species have evolved adaptations to darkness. Their ecosystem is based on chemosynthesis, which is basically getting energy from rocks.
