Short (<80-50 pages) book on futur projection

Dear readers,

I really love book that reflects on the (believable/fantastic) futur. Although this might be vague, I will exemplify.
I really like novel such as the last question by Asimov,
Other exemples would be le papillon des étoiles by Werber, or journey to the center of the earth by Jules Verne, despite older, qualifies.

I'm on vacation and would love if you could give me a great read of yours.

Thank you very much 🙂