I really wanted to like this story, but like so many sequels it was so different from the preceding book [Big Time] that I couldn't get into it. Greta was so aware in the first book, and there's no explanation of why she is so broken in this, If you liked this, read Big Time. If it was so-so, don't bother.
"Tom Corbett" was a joke, and I never watched or read any of the stories. I got these mainly because Willy Ley was the technical adviser for the series, but I hope Rockwell overrode him on things; I know Ley wouldn't have let some of the things pass if he had any control. Rockwell apparently had no idea how rockets worked [Newton's Laws of Motion were totally beyond his knowledge], as were properties of materials: they were going to get rich from copper for electronics uses, even though they said silver was cheap, and silver would be preferable to copper. I'm ignoring the fact that they now use gold [even better] for many electronics purposes. The purpose of the trip to Tara was to test an audio communicator, even though radio waves travel at the speed of light, while their ships are traveling through hyperspace, which allows them it ignore the limitation of light speed [unless I missed something and the communicator used something similar to ignore the limitation].
It's easy to see why Rockwell is ignored when people discuss SF writers. Compare him to H Beam Piper, who wrote at the same time, and see the difference. You can't even compare him to Robert Heinlein, who also wrote "juveniles" in his early years. His ignorance of science makes reading his stories difficult.