Cetus is an ancient constellation. Sometimes mistakenly called a whale, it is really Ketos, an ancient Greek term for a sea monster. It was drawn with the front end of a fearsome land animal with gaping jaws and the rear of a sea serpent. In the story of Cassiopeia and Andromeda, Ketos was sent by Poseidon to harry the coast of King Cepheus’ kingdom. An oracle told Cepheus to offer his daughter Andromeda as a sacrificial victim to the monster, but she was rescued by the hero Perseus. We can imagine Ketos swimming rapidly up the sky, past Pisces, to reach the chained Andromeda. 

It is a large constellation, but only has two second magnitude stars, Menkar and Diphda, with a scattering of third and fourth magnitude stars. The chart shown above is an attempt to connect its brighter stars, and looks vaguely whale-like. The chart above, and the similar one drawn by H A Rey, are actually the wrong way round. A pentagon of stars which included Menkar and Kaffaljidhma was traditionally the head of Cetus, rather than its tail. Diphda, the brightest star in Cetus (despite being Beta Ceti) forms a bright pairing with Fomalhaut (Alpha Piscis Austrini) in Pisces Austrinus, which was noted by the Arab astronomers (Fomalhaut being the first frog and Diphda the second frog; its name being Arabic for frog). It is a striking sight in southern Portugal, but hardly visible in Havering.

The most important object in Cetus is Mira (Omicron Ceti) [1], the famous variable star. It is a red giant which varies enormously between magnitude 3.4 and 9.3, with a period of 332 days. It is easiest to tell when it is at or near its minimum (although it is then hardly visible in a small telescope) because it has a companion star at magnitude 9.7, which is slightly dimmer. The only other easily observed object in Cetus is Kaffaljidhma (Gamma Ceti), a close double (mag. 3.5 and 6.2); usually seen as yellow and blue, or yellow-green and brown (or dark olive green). 49 Ceti [2] is a magnitude 5.6 star which will need binoculars to be seen in Havering. It is a young star with a protoplanetary disc which was discovered by the radio telescope array, ALMA. It contains a lot of atomic carbon which may be a result of comets colliding.