[GlassOuroboros]

While I cannot recommend any particular books, I can recommend that you look into the "Hard Science Fiction" genre. They are very realistic, yet still have a cool aspect of fiction. The Wikipedia page for Hard Science Fiction has a list of good books in the genre.

Besides that, off the top of my head, I would say books by Isaac Asimov (Foundation series) or Arthur C. Clarke (Space Odyssey series).

[henrikschroder]

My standing recommendation in the SciFi genre would be any Culture novel by Iain M. Banks. Truly utopian SciFi, and an interesting depiction of a post-labour, post-scarcity, post-human, AI-symbiotic, "human" civilisation.

It's not hard SciFi, but close. Banks really understood that spaceship battles are about mass, velocity and energy, and technobabble doesn't save the day.

[gpderetta]

> not hard SciFi, but close

I would say it is pretty much space opera (every single technology is handwaved away). It doesn't make it less awesome though.

[mercer]

That's fascinating! Do you know why this would be called 'space opera'? And could we also say things like 'western opera'?

[detaro]

I think for "simple" western movies the term was "horse opera", related is "soap opera", but in science-fiction it is not seen as such a negative term anymore and the definition has expanded to cover a wider range of works. Futuristic with not much in the way of technical details, hero figures, grand conflicts is roughly what makes a space opera now, and at least some of Banks' works fit right in there.

[jordonwii]

Another "hard sci-fi" suggestion: Seveneves by Neal Stephenson. Goes into a lot of detail about some potentially interesting things (moon science and orbital mechanics come to mind), if you enjoy that. I learned that I don't, but still really enjoyed it for the great story.