Enigma chain thread

[palou]

For your problem: one, considering that the astronaut would be the alien on the planet? Otherwise, I would not know.

The correct answer for mine is 20. Considering that all the numbers between 0 and 40 will have to be mentionned, (41 people, so 41 different answers) we can deduce that one person has shaken the hand of 40 people. However, the person having shaken 0 hands must obligatorily be married to him, as the first could not have shaken his hand otherwise, (since a handshake counts for both), and the first person needs to ahake all possible hands to get to 40. After that, there is equally a person that has shaken 39 hands. In a similar manner, the person he is married to must have shaken exactly 1 hand, as if someone else would have shaken only one hand, (which is obligatorily shaken with the guy that has shaken 40 hands), the person could not have shaken 39 hands, as he has to shake all possible hands excluding the 0, who could not have shaken his hand, to be able to come upon 39 hands. On so forth, only the middle value is left, for misses smith, as her husband was not interrogated, thus she is the only one not to have an interrogated person whom she could not have shaken the hand of.