‘Project Hail Mary’ brings a new kind of alien to the big screen

Science fiction nerds, rejoice: The long-awaited adaptation of “Project Hail Mary” is in theaters now. The 2021 book is considered one of the best science fiction books of the 21st century (and according to the New York Times, one of the best books, period). It follows failed molecular biologist and middle school teacher Ryland Grace on a solo journey to save the world from a microbial alien species that is slowly, but surely, dimming the sun.

While the film stars Ryan Gosling as our human protagonist, the real star of the show is Rocky, a five-limbed, Labrador-sized creature with no face that looks like a tarantula made of rocks. We talked to “Project Hail Mary” author Andy Weir, and astrobiologist Dr. Mike Wong, about Rocky’s biology, and how he bucks the trend for how we typically envision aliens.

Rocky on film

Rocky, an alien from the planet Erid, is very cute, thanks to puppet designer and performer James Ortiz. But was he what Andy Weir imagined him as he wrote the character?

“The truth is I don’t have a very visual imagination. So when I’m writing, the characters are just sort of blobs,” Weir said. “I knew that he’s got a thorax, and five legs, and there’s joints and three fingers at the end of each hand. But I couldn’t have told you whether his legs were skinny or wide, or if they were bumpy or smooth.”

Seeing the puppet design made everything click into place for Weir, who was more concerned with Eridian species morphology and biology. “ I spent a lot of time going down that rabbit hole because speculative evolution is fun.”

Rocky’s biology

Weir imagined Eridians as self-contained biospheres that operate without inhaling or exhaling. Instead, they’ve got a personal oxygen-to-carbon dioxide exchange system. That meant their communication style couldn’t be based on traditional mouth sounds.

“[Eridians] have basically air bladders that push across vocal cords back and forth to make sounds,” Weir said. “They have five of them because everything is pentasymmetrical in Eridian biology, because I arbitrarily decided it would be. And so they can make chords.”

The result is that Rocky sounds more like a whale than anything human-adjacent. Rocky and Ryland find ways to communicate via a fancy computer translation system, but it isn’t easy because, well, they’re aliens to each other.

“ I wanted [Rocky] to be completely incompatible with all things human,” Weir said. “Like, if you put an Eridian in a human air atmosphere, he’ll die. If you put a human in an Eridian’s atmosphere, he’ll die.”

Could aliens like Rocky exist?

Astrobiologist and planetary scientist Mike Wong is a big fan of Rocky’s non-traditional look, because it points to the fact that evolution is often random.

“Things like body plans, what kind of symmetry you have, those could be locked in early on due to a chance mutation,” Wong said. “And then from then on out, you’ve got fivefold symmetry instead of bilateral symmetry, or something like that.” But, he points out, the true breadth of possibilities for evolution could be much broader than what we see on Earth.

Weir agrees, and says the extreme differences between Rocky and human protagonist Ryland have parallels to life on Earth.

“Even on Earth, in our own biosphere, if you exchange the positions of a shark and a camel, they’re both gonna die,” Weir said. “So something that evolved on another planet is almost certainly not gonna be compatible with us.”

Worth the watch?

If you like big, bombastic, and beautiful science fiction, then absolutely. My main takeaway after leaving the theater was that this film is visually stunning, from the sets, to the depictions of space, to Ryan Gosling’s fantastic head of hair. “Project Hail Mary” is Science Friday-approved. 

— Kathleen Davis, SciFri Producer

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