Rhonda S. Halloran was a Human female who served in Starfleet in the 23rd century. By the mid-2270s, she had risen to the rank of vice admiral and worked at Starfleet Command on Earth. In 2275, Vice Admiral Halloran sent a message to the USS Enterprise informing them that they had been selected to test the inversion drive. In a private message to Captain James T. Kirk, she said that she had wanted the USS Raptor to be the one to test it. (TOS novel: The Wounded Sky)