Also known as Space black metal or Astral black metal.

Fusion of atmospheric black metal and space rock/space ambient
https://musicbrainz.org/genre/d14a4c4a-bea5-4b08-b945-59b048acd2d5
https://musicbrainz.org/genre/532dcf83-5641-446d-b007-51292b401650
https://musicbrainz.org/genre/cb058995-96b0-45ed-a3db-2f066bfe948d

https://www.wikidata.org/wiki/Q124099574

Some critics claim it has been around since 1994.
https://www.vice.com/en/article/mb73j3/cosmic-black-metal-is-as-weird-and-dark-as-it-sounds
https://www.decibelmagazine.com/2021/02/15/cosmic-black-metal-decibel/
https://daily.bandcamp.com/lists/bandcamp-cosmic-black-metal-list

RateYourMusic new genre suggestion looks like it will be approved:
https://rateyourmusic.com/admin/queue/hq/profile_details?id=57959&type=h&context=p

As usual, no Discogs link because they are always the last to add new genres.