While you may know me on Film Threat primarily as a film critic (which I also did for years at Ain’t It Cool News as Copernicus), I’m also a professional astronomer. Sometimes I also host TV shows, and I help to advise books and movies on getting the science right.
I’m thrilled to share our Science Vs. Cinema on Project Hail Mary. This is a special one because I was a science advisor on the book. On Science Vs. Cinema where I take a look at the science in movies, often talking to film creatives to see how they approached the science, but also to the subject experts in the fields they are covering to see if they got the science right. On the show, I got to interview the novel’s author, Andy Weir, who was also a producer on the film. I also talked to the screenwriter Drew Goddard about adapting the novel, and to astronaut Kjell Lindgren, who was an advisor for the movie.
Andy Weir called me with the idea for Project Hail Mary in 2018, so besides him, I’ve been eagerly anticipating the film longer than just about anyone on the planet. When I first heard the main ideas, I was blown away and thought it was an incredible setup for some mind-bending science fiction. I’m happy to say the film exceeded my expectations. Just like the book, it has amazing ideas, first contact with two alien species, high stakes, humor, great characters, and science is front and center. But it also has the extra dimension of bringing these amazing characters to life with great acting, music, and outstanding visuals.
Ryan Gosling stars as Ryland Grace in PROJECT HAIL MARY, from Amazon MGM Studios.
Photo credit: Jonathan Olley
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“Just like the book, it has amazing ideas, first contact with two alien species, high stakes, humor, great characters, and science is front and center.”
This article is adapted from the Science Vs. Cinema episode. It is substantially similar, but it does deviate. If you only have time to do one thing – watch the video! Let’s get to the science!
40 Eridani A
What about Rocky’s planet? Amazingly, the character of Rocky was guided by real-world astrophysics discoveries. In Project Hail Mary, Rocky’s homeworld is a planet around the star 40 Eridani A, which they call Erid. That star also happens to host Spock’s home planet of Vulcan in Star Trek. In 2018, astronomers announced the discovery of an exoplanet around the star, named 40 Eridani Ab. It was one of the first “super Earths” — it was about 8 times more massive than the Sun, and it was possible that it had a solid surface.
When he was writing Hail Mary, Andy Weir wanted to have Rocky’s homeworld be a real exoplanet, and 40 Eridani Ab was nice and close at about 16 light-years away. The only problem was it didn’t seem like it could support life… or at least life as we know it. The planet was closer to its star than Mercury is to the Sun, so water couldn’t be in a liquid state, at least if the atmosphere was like Earth’s.
Andy Weir thought… hmmm, well, at that orbit, if you made the pressure really high, you could have liquid water not boil away, so let’s make the atmospheric pressure 29 times that of Earth. That fits with the large mass of the planet. And the planet is close, so it has to be hot. As a result, we got a compact, rocky alien that could survive high gravity, pressure, and temperature. With that much atmosphere, maybe you couldn’t see its sun from the surface, just like on Venus — everything would be a haze. So then maybe they didn’t evolve eyes, and they just use echolocation.
