Project hail mary - andy weir
The story is told in two parallel planes, the real-time and the memory-time. Real time is on a spacecraft, where the sole survivor of the missions needs to find out what he's supposed to do after waking up from a long come. The memory-time slowly catches up with what was happening on Earth before the mission started.
The core of the story is that there's a life form that absorbs energy from the Sun, eventually lowering the amount of heat that reaches earth. Astronomers observe the same behavior in the entire neighborhood except one start, and there's where the mission is headed.
In the memory-time, we learn that all nations line up behind a Dutch scientist called Stratt, who has absolute power and resources. The astrophage eating the sun can also be used to release a gigantic amount of energy, which is what is needed to generate continuous acceleration towards the star that needs to be studied.
Ryland Grace, the protagonist, is a school teacher who gets involved with the project Hail Mary almost by chance and becomes an integral part of it. He is the one who survived aboard the ship and on whose shoulders rests the future of Earth.
In the space shuttle, Dr. Grace encounters an alien space ship, and Rocky is onboard. They start some friendly exchanges. It turns out that Rocky comes from a start also affected by astrophage and is looking for the same answers.
Most of the story in space revolves around how the two astronauts communicate and learn from each other. About evolution, spacecraft design, etc. Most importantly there's a heavy component about languages that may have been slightly overlooked by the author.
On Earth, the challenges revolve around melting ice caps to release methane and keep Earth warm for a little longer. Technical challenges in the use of astrophage, etc.
The mission in space eventually finds a solution to the problem and must send the information back to Earth. Of course, from a relativistic standpoint, time elapsed on the ship was less than on earth (continuous acceleration > g). The samples are sent back, so the anti-astrophage can be released and the Sun can be saved on time.
In space, when Grace was preparing to go back home, sees that the spacecraft of Rocky stops working and decides to go back to save him. Eventually, Grace ends up in Rocky's planet where he becomes a teacher.
The true unexpected turn in the story is that Grace was put on the space ship by force. The real scientist astronaut gets killed in an accident, and Stratt forces Grace to go on the trip. She puts him in a coma right before the trip and instructs the robot on board to administer a drug for him to forget and slowly remember what happened.
As a whole is a fun read. There are many engineering details embedded. The sad part is that the author decided to include explanations way too often. Either how to transform from normal units to imperial, etc. or explanations of very basic physics. If the book is for geeks, it should stick to it.
It would have been very interesting to see how this same story would have ended up if written by a linguist instead of an engineer.
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