Taurus (constellation) astronomers. Taurus hosts two of the nearest open clusters to Earth, the Pleiades and the Hyades, both of which are visible to the naked eye. At first magnitude, the red giant Aldebaran is the brightest star in the constellation. In the northwest part of Taurus is the supernova remnant Messier 1, more commonly known as the Crab Nebula. One of the closest regions of active star formation, the Taurus-Auriga complex, crosses into the northern part of the constellation. The variable star T Tauri is the prototype of a class of pre-main-sequence stars. Taurus is a big and prominent constellation in
Horologium (constellation) Horologium (constellation) Horologium is a faint constellation in the southern sky. It was devised by French astronomer Nicolas Louis de Lacaille in 1752, and it remains one of the 88 modern constellations. The constellation's brightest star is Alpha Horologii, an orange giant. R Horologii is a red giant Mira variable with one of the widest ranges in brightness known. Three star systems have exoplanets, while Nu Horologii has a debris disk. The French astronomer Nicolas Louis de Lacaille first described the constellation in French as "l'Horloge à pendule & à secondes" (clock with pendulum and seconds hand) in 1752, after