Project Hail Mary

The patient awoke to find himself strapped in a bed, barely able to speak or move.  A robotic doctor tended to him and administered cognitive tests.  He had been in a coma and was now suffering from amnesia.  Not good.  Worse, his two bunkmates were dead and in an advanced state of decay; he was in a coma for a long time.  As he explored his surroundings, he discovered that he was on a spaceship!  It turns out he knows a lot about space.  Using onboard instruments, he thought the sun looked a bit strange.  That's not the sun, it's a different star!  Holy moly, he was in another solar system!

Scientists discovered that something was eating the sun.  A single-celled organism has infected the sun and, if not stopped, would dim the sun by 10%; that would bring on an ice age and wipe out much of humanity.  After much investigation, scientists discovered that the organism had already infected neighboring star systems.  However, Tau Ceti was unaffected.  Why?  Project Hail Mary was launched to find out what made the Tau Ceti system immune to the sun-eating microbe.

The story takes place in the near future.  The narrative switches back and forth between the present in Tau Ceti and the past with the discovery of the sun dimming.  Dr. Ryland Grace had written a speculative paper on non-water-based life, which made him an ideal candidate to examine a newly discovered lifeform that somehow lived on the sun, not known to be water-friendly.  Soon, he became an important figure in the effort to reverse the sun's dimming, which must explain why he was in the Tau Ceti system.

Like in his other book, The Martian, science plays a major role.  Though some of the technology is more advanced than today, physics works correctly.  That first contact proves to be with a microbe is funny and also probably more likely than meeting Spock.  It is an entertaining read though the hero is diminished as the story progresses.  Why is a PhD teaching middle school science?  Why does he cry so much?  The more his amnesia faded, the less I liked him.  Kind of sad.  Nonetheless, recommended for any sci-fi fan.