Rereading Methuselah's Children. I still remember reading it as an 11-year old kid and being fascinated by the technical descriptions of how the pilots calculated courses and trajectories.
He was already setting up the problem in his ballistic calculator. Aside from checking the orbit elements of the New Frontiers in the Terra Pilot Lazarus could have done it in his sleep; satellite-matching maneuvers were old hat for any pilot and a doubly-tangent trajectory for a twenty-four hour orbit was one any student pilot knew by heart.
I couldn't wait for us to have personal space travel and being able to boast that I could calculate satellite-matching maneuvers!
The funny thing is that back in 1977 I was POSITIVE I would one day pilot a spacecraft. What seemed science fiction was a self-driving automobile:
Mary claimed her car from the robopark, guided it up the ramp and set the controls for North Shore. The car waited for a break in the traffic, then dived into the high-speed stream and hurried north. Mary settled back for a nap.
Or doing a three way video call!
The Administrator answered his call at once, although it was late at night in the longitude of Novak Tower. From the puffy circles under Ford's eyes Lazarus judged that he had been living at his desk, said Lazarus, better get Zack Barstow on a three-way. I've got things to report. By split screen, Barstow joined them. He seemed surprised to see Lazarus and not altogether relieved.
Heinlein predicted Teslas and Zoom in 1941!! But I still don't have a space pilot's license. Sigh.
CONCLUSION: Nowhere near as polished as his later triumphs, but Methuselah's children still is a fun interstellar romp. The dialogue is a great look at late Fifties / early Sixties slang and is corny at times, but the idea and political intrigue (particularly in the first half of the story) presage later work. Heinlein clearly identifies with the main character, Lazarus Long, as close to an archetypal figure as he ever created. There doesn't seem to be any point to the plot, which randomly ends...but then again, as Long muses, maybe that is the point of life, itself: Keep living and learning.
Note from the poster: Heinlein is a master, this was a really good, fun quick read - but nothing fluffy about it. There are more books about "The Families" and Lazarus Long (one of its members) and I plan to hunt down and read them all.
