Here is the full list of all 25 Astrologaster (Windows) achievements worth 1,000 gamerscore.
Coitus post consultatio
Recieve one letter of recommendation.
Complete Emilia Lanier's storyline.
Recieve two letters of recommendation.
Recieve three letters of recommendation.
Recieve four letters of recommendation.
Recieve five letters of recommendation.
Recieve six letters of recommendation.
Recieve seven letters of recommendation.
Recieve eight letters of recommendation.
Win a medical licence.
Complete the game.
Complete Avis Allen's storyline.
Complete Ricardo Ferraro's storyline.
Complete Nicholas Mugg's storyline.
Complete Robert Devereux's storyline.
Complete Thomas Blague's storyline.
Complete Alice Blague's storyline.
Complete Sybil Fortescue's storyline.
Complete Humphrey Bell's storyline.
Complete Emma Sharpe's storyline.
Complete Mary Payne's storyline.
Complete John Whitgift's storyline.
Complete Simon Forman's storyline.
Complete Lancelot Moore's storyline.