Beta Crucis, also known as
Mimosa or
Becrux, is the second brightest star in the
constellation Crux (after
Alpha Crucis or Acrux) and is the 19th
brightest star in the night sky. It forms part of the prominent
asterism called the Southern Cross, which appears on five national flags. Although Beta Crucis, "Becrux", is at roughly -60°
declination, and therefore not visible north of 30°, in the time of the ancient Greeks and Romans it was visible north of 40° due to the
precession of equinoxes, and these civilizations regarded it as part of the constellation
Centaurus. Its modern name,
Mimosa, which is derived from the
Latin word for "actor", may come from the flower of the same name.