I just finished The Martian II. Ryland Grace stars as the new Mark Watney in another fun Robinson Crusoe SF story. Waking from a protective coma aboard a spaceship, Grace can't remember his name, his life, or anything but maths. He's being fed by an annoying computer, and only when he is strong enough to remember his name and open a hatch, is he allowed to get on with saving Earth in PROJECT HAIL MARY.   Astrophage is a spacefaring microbe that a scientist named Petrova discovered to be eating the Sun's energy. As Grace gradually gets flashbacks (conveniently, they occur in date order) he recalls how he, a former scientist, and science teacher, managed to learn some of the properties of Astrophage, and so got roped into helping a woman named Stratt with top-level clearances, try to solve the problem.  But meanwhile, he's here, orbiting Tau Ceti, another infected star, looking for interstellar answers before Earth freezes. And he\'s not alone.   The similarities to The Martian are everywhere. Major planetary co-operation. Spaceships. Stranding. Music. Food for the spacefarer. One problem after another is to be tackled with physics and light engineering. Maguffins appear more frequently (a term for an invention we don't have yet, on which the plot depends), and Grace gets someone else to talk to, named Rocky, but that person is quite like himself, as they are on the same mission, so some readers will feel it's another return to The Martian, in which Watney talked to NASA engineers.   Andy Weir has been inventive, entertaining, and thoughtful. Do we need him to write a romance? We don't, but some deeper human feelings would have been good and would have rounded off the sulking science guy who couldn't handle negativity. Again, the main character has no family or close friends, nobody to miss him. Maybe this is why Grace gets on so well when he finally makes a friend. Rocky is one of the better elements of this story and will be loved by SF readers everywhere. Weir's second book Artemis was set in a Moon colony, and given the success of The Martian as a film, and the greater complexity of filming a whole lunar colony, compared to a greenhouse in a desert, he probably had film options in mind while writing PROJECT HAIL MARY.  I'll be looking forward to the big screen version. This packed narrative will also deserve re-reading to wrap the various viewpoints and threads. I love science fiction that is about science, especially when it doesn't have to involve intergalactic war. Earth has many problems, Andy Weir seems to be telling us, and we can only resolve them with giant, cooperative efforts.