Always been a fan of Vangelis. Have you heard
The City? It's pretty amazing I feel. And of course then there's
Oceanic and
Direct is a great one too. I also own
Spiral on vinyl - I love "To the Unknown Man". You should also check out
Heaven and Hell (was used as the theme music to Carl Sagan's
Cosmos) and
Les Apocalypse des Animaux for really relaxing ambient music.
Edit: I see Synthgirl has already put you on to
Heaven and Hell. GMTA!
Albedo is a good shout too. Apart from great music you also get interesting information about this ball of rock we live on.
https://www.youtube.com/watch?v=_Vc88E6j4qE
https://www.youtube.com/watch?v=GF_xSWzpcRY&t=2165s
https://www.youtube.com/watch?v=JNTaFnzFABU
https://www.youtube.com/watch?v=R9QHqpdczH0
https://www.youtube.com/watch?v=D97GVvAd5Nw
Synthgirl, I won't insult you by asking if you've heard Marillion and Pendragon, but try this Genesis-sounding newer band. Also, if you like 70s Genesis you should check out Big Big Train.
https://www.youtube.com/watch?v=JTbTLXPLPww
https://www.youtube.com/watch?v=czgRIvcnTeE