Bob Forward describes things that are theoretically possible -- not ruled out by our current understanding of science -- but are so far advanced from our current technology that they seem like magic -- or science fiction -- to us today. But remember, most of the technology we have today would have seemed like black magic only a century ago.
Arthur C. Clarke's Third Law
Chapters of non-fiction, to describe the hard science, alternate with short science fiction stories, to help illustrate the potential technologies. There are also many references, to aerospace and astronautics technical journals, where some of the engineering designs are to be found in fuller technical detail.
Bob Forward, renowned for his ultra-hard SF, excels at weird alien physiologies. In Dragon's Egg he gave us small, ultra-dense, fast living creatures on the surface of a neutron star; in Rocheworld it was strange liquid creatures in the joint sea of a double planet. Now in Camelot 30K we have really cold aliens.
Life has been discovered on Ice, one of the perpetually frozen planets in the Oort cloud that surrounds our solar system. The surface temperature is only 30 degrees above absolute zero, a temperature at which nearly everything is frozen solid. So how can these strange creatures, the keracks, survive?
This is essentially a hard science puzzle story. We get treated to lots of low-temperature chemistry, especially of fluorocarbons, as the observing human scientists try to figure out the secret of the keracks' energy source.
As usual with Bob Forward, read this novel for its hard science, not for its characterisations. The kerack society has recognisably human features --- a mediaeval communist aristocracy --- with only a few nods towards alienness; the human observers have few problems communicating with the keracks. And I'm not sure I believe there could an evolutionary route to the energy source that is finally revealed, especially given the length of a kerack 'generation'. But never mind: there is some fun science along the way.
A crew of six is sent to Saturn to test whether it's possible to mine the atmosphere of helium and produce the valuable fuel "meta". But when they get there, their ship crash-lands on the back of one of the enormous flying Saturnian "rocs", or rukhs, which turn out to be intelligent.
Another Forward novel heavy on the science, light on the characters. Unfortunately, this time the science isn't really that interesting. It's mostly just orbital dynamics (the problems of getting down to Saturn's atmosphere, and the even bigger problems of getting back again; not the mind-blowing super science that is Forward's trademark), and a bit of alien physiology. Yet the aliens aren't that alien (except bodily) -- the humans learn to communicate with them with amazing ease -- although they are more real as characters than the cardboard flat humans. And given the build-up of the Green activist involvement, the problem of continuing the mining operation given the natives' intelligence is "solved" with almost insulting ease.
So, worse characterisation than usual, not sufficiently offset by good physics.
['Christmas Bush' fractal robot; Flowen: alien mathematicians on a double planet]