Astrology

Requirements
Astrology requires 50 science.

3 science: 17 turns until complete

4: 13

5: 10

6: 9

7: 8

8: 7

9: 6

10-12: 5

13-16: 4

17-24: 3

Leads to
Astrology leads to Calendar, which makes it even more of a religious technology!

Unlocks
Astrology unlocks Stonehenge and the Small Wonder: National Cathedral, which are both religious. It also has the Church (Holy Site in civ 6, Lavra playing Russia) which can also focus on faith.