I'm gonna apply for Birkbeck. I love its central London location, in Bloomsbury next to . I went to look at Birkbeck, it's just a normal old building, but inside it was cosy, and outside it was surrounded by UCL, SOAS, the University of London Senate Library, etc, so there were many students. I'll be doing my own study in the day time in that area, a few libraries to choose. I'm ok with Birkbeck's evening classes, because that will also give me the option to work part time during the day if I want. I want to work hard for my master's (I didn't study properly during my bachelor's years), and I'm impressed by the care and responsiveness of a programme director who has been replying to my questions. That same person will also teach 2 or 3 modules in my chosen master's, so I'm looking forward to become a student again.
Your shortlisted course Astrobiology sounds cool. Mine is just a normal master's which can be found in other universities too but the knowledge/skills will be very useful for my future.