Space rock is characterized by drawn-out songs, often repetitive,
with a dreamy, spacey feel, often enhanced by subtle electronics.
It's not really a metal genre per se (certainly few if any of the bands
featured here would consider themselves heavy metal), but these bands can
be quite heavy, with a psychedelic feel similar to some stoner rock bands.
Hawkwind, a band that's been around since the beginning of time and
who has released approximately seven billion albums (and who may yet
someday be featured on these pages) has to be considered one of the
founding fathers of the genre.