How Much Science Fiction is ‘Project Hail Mary’?

Ryan Gosling’s new film, Project Hail Mary, based on the acclaimed novel by Andy Weir, has audiences captivated with its blend of suspense, humor, and surprisingly plausible science. The story follows a middle school science teacher who awakens with amnesia on a desperate, one-way mission to save Earth from an existential threat: a sun-eating microbe. But how much of this interstellar drama holds up to scientific scrutiny? The premise, while fantastical, touches on real astrophysical concerns and biological possibilities, prompting a fascinating discussion about the boundaries of scientific realism in science fiction.

The core problem in Project Hail Mary centers around “astrophages”—microorganisms that consume stellar energy, causing stars to dim. This dimming, if significant enough, could plunge Earth into a new ice age. While the concept of microbes consuming stars is novel, the underlying concern about stellar luminosity and its impact on Earth’s climate is rooted in genuine scientific understanding.

Stellar Dimming and Earth’s Climate

According to science journalists Tina Hesman Saey and Carolyn Gramling, who attended an early screening of the film, the astrophages cause the sun to dim enough to drop Earth’s temperature by 10 to 15 degrees over 30 years. As they point out, past ice ages weren’t solely caused by changes in the sun’s luminosity, but likewise by variations in Earth’s orbit and tilt. Yet, a 10 percent reduction in the sun’s energy output within three decades would have a significant cooling effect.

The speed of the dimming is a key point. The sun’s luminosity naturally increases by about 10 percent every billion years. The astrophages accelerate this process dramatically, creating a crisis timeline that drives the narrative. While a rapid decline in solar output isn’t something scientists currently observe, the film uses this accelerated timeframe for dramatic effect, a common practice in science fiction.

The Biology of Astrophages: Could Microbes Survive in Space?

The idea of microbes thriving in the extreme conditions of space and on the surface of a star is perhaps the most far-fetched element of the story. However, it’s not entirely without precedent. As the journalists note, Earth organisms like moss spores and tardigrades have demonstrated remarkable resilience in the vacuum of space, surviving in a state of suspended animation.

However, the astrophages in Project Hail Mary are not merely surviving; they are actively living, reproducing, and traveling between stars. This requires a unique set of adaptations. Weir drew inspiration from algae and mold, envisioning the microbes absorbing solar energy for propulsion and breeding on planets with carbon dioxide-rich atmospheres, like Venus.

While no known Earth organism can withstand the combined extremes of intense heat, cold, vacuum, and radiation, microbes are renowned for their adaptability. Certain archaea and bacteria thrive in incredibly harsh environments – extreme temperatures, high pressure, and acidic conditions. The possibility, however remote, of a microbe evolving to survive such conditions isn’t entirely outside the realm of biological plausibility.

Xenonite: A Conveniently Powerful Material

The film introduces “xenonite,” a material composed of xenon that possesses extraordinary properties, allowing for rapid construction and manipulation. This is where the science leans heavily into the realm of science fiction. Xenon is a noble gas, meaning it’s chemically inert and doesn’t readily bond with other elements.

Creating a solid structure from xenon requires extreme conditions – either incredibly low temperatures or immense pressure. As the experts explain, scientists have crystallized xenon, but only under extreme laboratory conditions. The ability to manipulate xenonite with ease, as depicted in the film, remains firmly in the realm of fictional technology. It serves a similar purpose to “unobtainium” in Avatar or “vibranium” in the Marvel universe – a plot device that enables the story’s progression.

The Importance of Scientific Inspiration

Despite its fantastical elements, Project Hail Mary demonstrates a commitment to grounding its science fiction in real scientific principles. Andy Weir’s approach, as he himself has stated, is to start with plausible scientific concepts and then extrapolate, pushing the boundaries of what’s currently known. This approach, combined with compelling characters and a gripping narrative, is what makes the film both entertaining and thought-provoking.

The film’s success also highlights the public’s appetite for science-based storytelling. By sparking curiosity about astrophysics, microbiology, and materials science, Project Hail Mary encourages viewers to engage with the wonders of the natural world and the possibilities of scientific discovery.

Project Hail Mary isn’t about predicting the future; it’s about exploring the potential consequences of scientific challenges and the power of human ingenuity to overcome them. It’s a reminder that even the most far-fetched ideas can be rooted in a foundation of scientific curiosity and imagination.

What’s next? As our understanding of astrobiology and extreme environments continues to evolve, the line between science fiction and scientific possibility may turn into increasingly blurred. Ongoing research into the resilience of life in extreme conditions, as well as the search for extraterrestrial life, could one day reveal discoveries that seem as fantastical today as the astrophages of Project Hail Mary.