Books

Children of Time from Adrian ~~Tartovsky~~ Tchaikovsky

Obviously both Weir's other books, The Martian and Artemis.

Also recommend the Silo book series by Hugh Howey. Not nearly as hopeful or optimistic, but there's a similar very strong vein of problem solving / human ingenuity just like in Andy Weir's work.

I liked the Bobbiverse series, starting with We Are Legion (We Are Bob) by Dennis E. Taylor. The first 3 books were great. IMO the 4th is ok, and currently listening to the 5th. Fun fact, the narrator for the Project Hail Mary and Bobbiverse series audiobooks is the same - Ray Porter, who fantastic.

Uh the martian

Well, first of all, "The Martian" by the same author.

If you liked Project Hail Mary, then you should read the Bobiverse series by Dennis E. Taylor. The premise is as follows:

Bob is dead. Long live Bob.

Bobiverse is an example of hard science fiction, with similar limitations to what PHM uses. The primary conceits that go beyond what's currently assumed to be possible are:

1. the assumption that it is possible to simulate consciousness using electronic media
2. the existence of some method of interacting with the fabric of reality to warp spacetime through a reactionless drive (here called "subspace theory"). This assumption allows for interstellar travel over reasonable time scales (but not superluminal travel) and, later, communications. Think a combination of the "Ansible" and the Bussard ramjet from "Tau Zero"
3. the fantasy that most people have comprehensible reasons for their actions.

E: I also wish to advocate for Children of time and, if you have additional spare time, Seveneves.

If you liked the “astronaut(s) on a distant world do science and meet interesting aliens” aspect Robert L. Forward's Camelot 30K and his Dragon's Egg and Rocheworld series might have a similar vibe.

Maybe also Iain M. Banks' The Algebraist or The Player of Games, though they're much further from “hard” science fiction and focus on the characters rather than the science.

Also maybe Larry Niven's The Mote in God's Eye? Maybe somewhere between the previous ones when it comes to science I'd say.

Or possibly James P. Hogan's Giants aka Minerva series, starting with Inherit the Stars..? It ends up a bit space opera-y, but the first books are about astronauts solving a mystery on the Moon...

(And if you get into that you might also enjoy Frederik Pohl's Heechee saga, starting with Gateway...)

Seveneves

Old Man's War by John Scalzi

In case it helps any, I made a post with a giant number of spoiler-free short reviews of SF and fantasy books, including most of the ones mentioned here (might have to click the links to the earlier posts for a number of them).

If you’re looking for empathy and kindness with an alien species, check out the Wayfarers books by Becky Chambers.

I have heard that "The Expanse" is a very good book series. Tho I haven't watched the series or read the books.

Three Body Problem is a great tv-series that are also based on books. If I recall correctly the author of Three Body Problem won the sci-fi award when he released that book.

Depends on what parts you liked most.

I have currently almost finished "The Forge of God" by Greg Bear.

It is a "Earth is threatened by a cosmic plague" type of story with strong science background and some truly alien alien encounters and leaves you in the dark about what the heck is actually going on for a long time.

But it is much more serious and lacks the light-heartedness of Hail Mary.

Can recommend it nonetheless.

A deepness in the sky

The Mote In God's Eye by Larry Niven and Jerry Pournelle

I listened to Project Hail Mary on Audible. Then eventually it recommended The Expeditionary Force series of books narrated by R.C. Bray.

I am on book 8 now... Can't stop.

Contact by Carl Sagan

While not knowing what you liked about Project Hail Mary, it's hard to suggest anything more than what has already been mentioned. A much darker look at space and aliens would be Stephen R. Donaldson's Gap Cycle. I would like to second a vote for A Deepness in the Sky.

Haven't read or watched ‘PHM’, but I've heard that Kim Stanley Robinson's ‘Mars’ trilogy is sorta comparable to ‘The Martian’, which latter is being recommended in the thread. Robinson is known for doing tons of research for his books and writing very realistic ‘hard’ sci-fi.

All I’ll say is the movie was a great adaptation of the book. Neither takes away from the other and it’s worth doing both

Titan by Ben Bova. It kept me awake all night turning pages.

Looking it up to confirm the author, I literally just learned that it's part of a series. Off to see dear Anna I go.

Old Man's War by Scalzi. A lot like heinlein used to write.

The Martian

Not a book, but an old 60s movie, Robinson Crusoe on Mars:

https://youtu.be/Twa8jKrIWE0

"Dragon's Egg" is a great little book written by a physicist/aerospace engineer and it shows.