Cetus

Cetus is a constellation in the southern celestial hemisphere named after the sea monster Cetus from Greek mythology. It is one of the 88 modern constellations and lies largely south of the celestial equator.

In astronomical terms, Cetus is relatively large but contains many faint stars. The brightest star is Beta Ceti, known as Diphda, with Alpha Ceti called Deneb Kaitos among its brighter stars. The constellation contains several notable deep-sky objects, the best known being Messier 77 (NGC 1068), a bright Seyfert galaxy. Modern surveys have cataloged additional distant galaxies and nebulae within Cetus.

Mythology: In Greek myth, Cetus is the sea monster sent by Poseidon to devour Andromeda, who is rescued by the hero Perseus after slaying Cetus.

Name and history: The name Cetus derives from Latin for a sea creature or whale. The constellation was described by ancient astronomers including Ptolemy and has since been retained in the modern list of 88 constellations.

Visibility: Cetus is best observed from the southern half of the Earth, where it is visible in the evening sky for parts of the year; from northern latitudes it appears lower on the horizon and is relatively faint.