Interestingly, astrologers have made significant contributions to the history of timekeeping. Since they really care about clock changes, time zones, mean sola

Interestingly, astrologers have made significant contributions to the history of timekeeping. Since they really care about clock changes, time zones, mean solar time, and exactly when these things took effect, they've done a lot of good helping us better document that history. (It shows up in the Unix TZ project)