The Only Rocky Explainer You Need For Ryan Gosling's Project Hail Mary

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Thanks to its introduction of the creature known as Rocky, "Project Hail Mary" needs to be added to the list of great alien movies out there. Looper praised "Project Hail Mary" as a "stunning space adventure," and plenty of viewers have already seen Ryland Grace (Ryan Gosling) search for a way to save Earth with his new interstellar buddy. The film does a great job of explaining what Rocky's all about, but in case you missed anything, watch Looper's video above for a quick recap.

Rocky hails from the planet Erid in the 40 Eridani star system, and his world's sun is also dying from the presence of the astrophage organism, putting his civilization at risk. Both Rocky and Grace have traveled to Tau Ceti, which appears immune to the astrophage, to determine why that star is not affected. But first they need to learn how to communicate with each other, since Rocky speaks in a series of musical tones. Starting with numbers, Grace records Rocky's tones and associates them with various concepts, constructing a rudimentary way to translate Rocky's language. 

Of course, language isn't the only difference between the two astronauts. Rocky is made of a rock-like matter, the explanation of which is detailed in the "Project Hail Mary" novel. The surface pressure on Erid is 29 times that of Earth, and the atmosphere is mostly ammonia. That's why Rocky requires protection on Grace's ship: oxygen isn't good for him. 

Grace soon learns that Rocky and all Eridians lag behind humans in certain areas. Initially, Rocky has no idea about relativity and radiation, which would seem odd at first for a space-faring species. Albert Einstein's theory of relativity suggests that time and space are not fixed concepts but instead change based on one's frame of reference. It's heavily reliant on light, and since Eridians don't have eyes and don't perceive light, it's understandable why they might not be able to grasp these ideas.

Radiation is also a pretty massive oversight — it's responsible for all of Rocky's crew dying before reaching Tau Ceti. Rocky only survives because his quarters are close to the astrophage. Since the astrophage eats energy from stars, it makes sense that it could consume other types of radiation to keep Rocky safe.

Despite these gaps in knowledge, Rocky is an outstanding engineer who immediately proves why he was a great pick for the Eridian mission. Not only does he make his little hamster ball to traverse Grace's ship, but he constructs models to communicate with Grace originally. He also creates a lengthy chain so that they can go "fishing" for whatever's eating the astrophage on the planet they dub "Adrian." Although Rocky is a completely new type of alien compared to what we've seen in other movies, making him part of some of the more confusing moments in "Project Hail Mary,"  everything gets explained pretty easily. If you have more questions, refer back to our video at the top.