In July, Richard Branson went up to the edge of space in a rocket plane, just pipping Amazon boss Jeff Bezos, who rose in his penis-shaped spacecraft nine days later. At least Bezos, or rather his company Blue Origin, had the honour of blasting none other than William Shatner 60 miles up in October. Space is cool again. But why did we abandon it for so long?

That’s one of the questions addressed by Colin Burgess’s splendidly nerdy history of the prior golden age of spaceflight, The Greatest Adventure (Reaktion, £25): from the Soviets shocking the world with the launch of Sputnik 1 in 1957, and then winning most of the landmarks of the space race thereafter, before the US put human beings on the Moon in 1969. After that, the great Earth public apparently just got bored with yawnsome moonwalks. Now, we have the antics of billionaires to make space great again.

Just as alien as anything we might imagine finding in space are the lifeforms – from vampire squid to “bone-eating zombie worms” and crabs named after David Hasselhoff – that inhabit the vasty deep of our oceans, some living in waters so inky black they are called the “Hadal zone” after the God of the underworld. Marine biologist Helen Scales’s The Brilliant Abyss (Bloomsbury, £16.99) is a literary bathysphere enabling us to explore this final frontier from the comfort of dry land, and a passionate plea for us to preserve ocean biodiversity, even if just for our own good.

One of its strange treasures, glorying in the name of the “four-eyed spookfish”, also stars in Sentient (Picador, £20), Jackie Higgins’s eye-opening account of the often bizarre or superhuman sensory systems of other animals, from Hades-dwellers to Arctic owls.

We’ll know if ocean biodiversity is failing if the seas increasingly harbour huge, choking blooms of jellyfish: this being one of the signs that we will have entered, if not the end times exactly, “a new era of slime”. So warns Susanne Wedlich’s Slime (Granta, £20), an enjoyably icky guide – slime, she says, has a “lusty frisson” – to all that oozes and squelches, from primordial microbial slime to the trails of slugs, slime moulds, your own bodily mucus, transparent squids and a clever if disgusting animal (the hagfish) that won’t stop using slime as a weapon.