Books like Orphans of the Sky
Robert A. Heinlein
Orphans of the Sky is 128 pages, about 2 hours 21 minutes at 250 words a minute.
12 books to read next
How long each takes
Gateway 5.7 h 
Dawn 4.7 h 
Tau Zero 3.5 h 
The Hitchhiker's Guide to the Galaxy 4.0 h 
Star Trek - Log Five 3.6 h 
Earthfall 7.0 h 
Cities in Flight 11.1 h 
Nightflyers 4.0 h 
The Skylark of Space 4.1 h 
When Worlds Collide 6.3 h 
The Entropy Effect 4.1 h 
Probe 6.3 h Bar height shows length. Estimated at 250 words a minute.