The problem with the other five is that they disappeared without trace. Which could be a good thing, if you like early Asimov. The Gift of Unbinding. Paula S. Jordan. There are tensions on Earth as those leaving to seek adventure off-planet are seen as taking with them part of Earth's heritage.
Individuals also face heartbreaking separations.
Fairly cumbersome press conference technique to air the debate, and a quite creaky dramatic ending. Not one of my more enjoyable reads of recent months.