New Age and esoteric literature often mention Ashtar or Ashtar Sheran, who allegedly is an extraterrestrial of higher dimensional being, or Ascended Master, who is the administrative head of the Ashtar Command.
According to some he is energetically connected to Venus.
Sometimes he is referred to as 'Commander,' which does not seem to be a hierarchical term, but more of a way of expressing respect for him.
Lots of channels claim to be channeling Ashtar Sheran.
Not that the first person to ever mention receiving telepathic messages from Ashtar was George Van Tassel (in 1952).