“Project Hail Mary” is an sf novel by Andy Weir. It’s currently finishing off a theater run as a motion picture made by Amazon (MGM). And in fact, this is Weir’s second book to be turned into a motion picture (the first one was “The Martian”).
Just to start with the most important question, I think this is an excellent book.
(Spoiler Alert – Skip down to last paragraph to avoid spoilers and read recommendation)
My review will have spoilers but I think I’ll be cagey about some of the plot elements because they’re pretty important to the way the story unfolds for the reader and I think they shouldn’t be sacrificed for the sake of my plot synopsis.
The book’s protagonist is Ryland Grace; a biology PhD who now teaches Middle School science because a paper he wrote about the possibility of extraterrestrial life in the absence of water was severely criticized. As the story unfolds an autocratic European Space Agency administrator named Eva Stratta whose been given almost unlimited authority commandeers Ryland into a multinational science and engineering project that is studying a mysterious non-terrestrial organism that is absorbing an enormous amount of energy from the sun and threatens to throw the Earth into a cataclysmic ice age.
Ryland discovers that the lifeform (which he names astrophage) has a life cycle which sees it looping around between basking close to the sun in order to store up enormous energy traveling to Venus, reproducing in the atmosphere of Venus and then returning to the neighborhood of the sun. And it travels back and forth in this cycle at speeds approaching c (the speed of light). And the explanation for this capability is that astrophage can convert energy into matter and matter into energy. There’s some hand-waving about neutrino production creating matter/anti-matter annihilation but of course there’s nothing that makes any sense. Anyway, the astrophage is increasing its numbers asymptotically and within thirty years Earth will freeze and mankind will disappear.
And it is discovered that all of the stars in our neighborhood are also dimming because of astrophage. All except one Tau Ceti. So, a star ship will be built by the combined technical skills of humanity and staffed with a crew of three including a scientist trained on the current knowledge about astrophage and hopefully they will discover why Tau Ceti is immune to the dimming and use this to find a cure for our solar system. And the star ship is powered using astrophage as fuel. Well, actually the light that the astrophage produce for motion is the propellant pushing the ship through space. Unfortunately, in the short window they have to create the ship and breed the enormous amount of astrophage needed, they cannot make enough for a round trip. This is a suicide mission (thus the name “hail Mary”).
And in order to keep the crew from killing each other in the tight confines of the ship for four (relativistically speaking) years, they are in a coma state. When the ship reaches Tau Ceti, Ryland is awakened and doesn’t remember who he is or where he is or why. He discovers that aside from robotic presences he is the only living human aboard. His two crewmates have long ago died during their coma states.
Gradually Ryland’s memory returns and he realizes that he must carry out the mission unassisted by the deceased pilot and engineer. Slightly later on he realizes that another star ship is in his neighborhood and he discovers that the inhabitants of another local star system (40 Eridani) have also sent a mission to Tau Ceti to solve the problem of astrophage. The alien is a sort of five-legged giant crab with an outer shell of metallic minerals. His atmosphere is ammonia at twenty-nine atmospheres and 200°C and so Ryland cannot go into his ship but must allow the alien to come to the Hail Mary in a protective suit.
The remainder of the book is a journal of Ryland and Rocky (the name he gives the Eridian engineer who is the only surviving member of the 40 Eridani mission) learning how to understand each other and cooperate to combine their highly complementary skill sets to solve what should be an impossible problem; translating the resistance of the Tau Ceti system to astrophage into a practical solution for Earth’s sun and 40 Eridani. And after many setbacks and several acts of selfless friendship by both partners they overcome the challenges and solve the problems and save Earth and Erid (Ryland’s name for Rocky’s home world). Now Rocky’s ship has an enormous surplus of astrophage and he is able to provide Ryland with enough fuel for a return trip to Earth. But after they separate for their voyages home Ryland discovers that a flaw in a containment tank will mean that Rocky’s ship will be out of fuel and doomed. Ryland reverses course and rescues Rocky and returns him to Erid in the Hail Mary and must therefore abandon his own return to Earth. He is able to send the solution to Earth’s problem (another single cell lifeform that Ryland dubs Taumoeba that eats astrophage and can be inoculated into the atmosphere of Venus) in four robot ships that will return to Earth on their own. In the last scene of the book Ryland is living in a special enclosure on Erid that protects him from the atmosphere, temperature and pressure conditions that would kill him instantly. But he has his friend Rocky around to keep him company and he has returned to his former occupation as a school teacher to Eridian children.
Okay. This guy Weir doesn’t kid around when it comes to detailed scientific descriptions. He’s got two different artificial gravity mechanisms (centrifuge and continuous acceleration/deceleration travel) and he describes their successful and unsuccessful usage in the story. He goes into gory detail to show how his astrophage can be used in a stellar drive. He goes into gory detail to describe his efforts to get Taumoeba to “evolve” into a population that will survive the atmospheres containing nitrogen on Venus and the planet near 40 Eridani. He goes into gory detail to discuss his efforts to isolate and remediate the contamination of his fuel by Taumoeba. This guy love technobabble. But I guess most people reading science fiction love technobabble too so it’s a forgivable sin. The other thing I notice is that Weir writes characters that correspond to millennials. They’re much more touchy-feely and prone to virtue signal than I care for. In other words, he’s writing for a modern audience, not a caveman like me. In fact, even though she’s very much a girl-boss, the character I most closely relate to was the autocratic administrator, Eva Stratta. My verdict is this is a very inventive and entertaining science fiction story and well worth the reader’s time. I highly recommend it.