As Naomi and her fellow teen astronauts investigate the fate of their predecessors on the Europa colony, back on a deteriorating Earth, Leo works with a renegade scientist to warn the crew about hostile extraterrestrials. Leaving Earth behind is hard, but what's ahead, on Europa, could be worse. The International Space Training Camp continues to hide the truth about what happened to the last group of astronauts who attempted a similar colonization...

So far the AstroNuts have failed to find a suitable planet, but NNASA has come up with a new plan: send the the four animal astronauts back through time on Earth where they are to contact early homo sapiens and somehow set them on a path to a sustainable future--trouble is, humans seem inferior to many of the other species (especially the wolves), so the AstroNuts come up with a Survival of the Fittest Olympics, hoping that with a little help the...

Carbon dioxide is out of control on Earth, and the fate of humankind rests in the paws of four experimental, untested Animal Astronauts (AlphaWolf, SmartHawk, LaserShark, and StinkBug) who are seeking another habitable planet; first destination is the Plant Planet which at first looks perfect, except that the abundant plant life can think for itself--and it thinks that it really does not like the AstroNuts.