Pun Salad

Another book down on my reread-Heinlein project. Only five left to go! It's a juvenile, and I don't think I've read it since I was a juvenile. But I still remembered the basic plot line. The Kindle version has some minor transcription bloopers.

The solar system has been conquered; there are even settlements on Pluto! (Brr!) But mankind has run out of room on Earth; population is coercively controlled. Although there's "torch ship" continuous-thrust technology available to allow practical travel to nearby stars, exploration is stymied due to the communication problem: even if you could punch through a radio signal back to Earth to report your results, it would take years for that signal to be received.

Solution: it turns out that telepathic communication between twins is "instantaenous" (take that, Einstein) and it doesn't fade with distance either. Teenage twins Tom and Pat are tested, and (after some drama), Tom gets picked to travel to some nearby stars on the Lewis and Clark, reporting back to Pat on Earth.

Complication: Einstein is correct about time-dilation effects. As the ship accelerates to near-lightspeed, many years pass on Earth while only days go by on board; Pat ages much faster than Tom. This leads to some strife, but (fortunately) relatives can be taught the telepathy trick as well.

I remembered disaster striking the mission; what I didn't appreciate at the time was the sheer horror involved in Heinlein's description as it unfolded. That was kind of unusual for him, I think.

This is one of Heinlein's later juveniles, and he really hit his stride here. Yes, there are the usual Heinlein elders, speaking Heinleinian wisdom to wet-behind-the-ears Tom. Par for the course. But Tom grows up as the mission goes on, and discovers things about himself, and also the nature of duty.