They are usually refered to seperatly as Sailor Alpha Centauri, Sailor Beta Centauri, and Sailor Proxima Centauri, but the full titles are as followed: Star Sailor Gaurdian Centauri Alpha. Star Sailor Gaurdian Centarui Beta, and
Star Sail Gaurdian Centauri Proxima. Each has thier own personaliy: Alpha is the leader, level-headed and deturmined, Beta is a born fighter, and Proxima is very sweet and calming.
These three were origanally soilders in the Zodiac Wars. After the end of it, however, which turned out to be the death of almost all of the Star Senshi, the Centauri Gaurdians have been placed in charge of protecting the secrets of the ages. It was sworn among them that no other but those with the powers of the Stars would know the truth about the Wars, and thus it stayed...Until the Bright Zodiacs came to find out the truth about thier past.
The three Centauris attack with musical instruments. Proxima's gong can petrify the enemies, much like Capricorn's Horn. Alpha's flute can control the elements around them to her whim. And Beta's harp sends out pulsing waves that literally blow the enemy away! They're a destructive force, and as close as ever to each other. They will never abandon thier post.
The Centauris do not have 'normal' forms. They're always in full transformation.