Deneb Kaitos (also called Beta Ceti and Diphda) ranks as the most brilliant star in the constellation Cetus the Sea-monster, shining on par with Polaris, the North Star. Cetus’s variable star Mira may brighten up enough on occasion to match Deneb Kaitos in brightness, though only extremely rarely, because Mira usually remains much too faint to see with the unaided eye.

It’s easy to locate Deneb Kaitos if you’re familiar with the Great Square of Pegasus. Locate the star by drawing an imaginary line through the two Great Square stars Alpheratz and Algenib.

Deneb Kaitos never climbs very high in the sky at our mid-northern latitudes. As a rule of thumb, Deneb Kaitos soars highest in the southern sky when the Big Dipper falls lowest in the northern sky (or beneath the horizon). If it’s easier for you, refer to the W or M-shaped constellation Cassiopeia the Queen. She swings high over Polaris, the North Star, as the Sea-monster’s tail star swings farthest up from the shore of the southern horizon.

Deneb Kaitos shines highest in middle November, at about 9 p.m. local time. The stars return to the same place in the sky about 2 hours earlier with each passing month (or four minutes earlier with each passing day). In middle January, look for Deneb Kaitos to reach its high point around 7 p.m. local time. On February evenings, this star drifts into the southwest sky, and disappears from the evening sky by March.

At nearly 100 light-years distant, Deneb Kaitos is a giant of a star, sporting a diameter 17 times larger than the sun’s. Check out this star with binoculars sometime and note its orange complexion. The orange color indicates a rather low surface temperature, and also lets us know that this star is entering into the autumn of its years.