Cetus

Template:Infobox Constellation Cetus (a name from Greek mythology, referring to a Whale or Sea monster) is a constellation of the southern sky, in the region known as the Water, near other watery constellations like Aquarius, Pisces, and Eridanus.

Contents

1 Notable features 2 Notable deep sky objects 3 History and Mythology 4 Stars 5 External links

Notable features

This constellation's most notable star is Mira (ο Ceti), the first variable star to be discovered. Over a period of 331.65 days it varies from magnitude 2.0, one of the brightest in the sky and easily visible to the unaided eye, to 10.1 and back again. Its discovery in 1596 by David Fabricius further dented the unchangeability of the heavens and lent support to the Copernican revolution.

Other stars in the constellation include the α star, Menkar; the β star, Deneb Kaitos, brightest in the constellation; and τ Ceti, the 17th closest star to Earth.

The ecliptic passes very close to the constellation. Some of the planets can be in this constellation for brief periods of time. The asteroid 4 Vesta was discovered in this constellation in 1827.

Notable deep sky objects

Cetus lies far from the galactic plane, so many distant galaxies are visible, unobscured by dust from the Milky Way. Of these, the brightest is M77, a 9th-magnitude spiral galaxy near δ Ceti.

History and Mythology

This constellation has been known since antiquity. In Mesopotamia, it was identified with the primordial cosmic female principle, the sea-monster Tiamat.

In Greek mythology, together with the constellations above it, of Andromeda, Cepheus, Perseus, Cassiopeia, and possibly Pegasus), this may be the source of the myth of the Boast of Cassiopeia, with which it is usually identified.

In certain earlier Greek mythology, it also represented the gates (and gateposts) of the underworld (considered to be the area under the ecliptic). As such, together with other features in the Zodiac sign of Pisces (including Pisces itself, as well as prominent stars behind Cetus), it may have formed the basis of the myth of the capture of Cerberus in The Twelve Labours of Herakles.

Stars

Stars with proper names:

• Menkar or Menkab [Mekab] or Monkar (92/α Cet) 2.54

  < منخر minxar nostril

  < منكب minkab shoulder

  < (?) منقار minqār peak (snout)

• Diphda [Difda al Thani] or Deneb Kaitos or Rana Secunda (16/β Cet) 2.04

  < الضفدع الثاني ađ̧-đ̧ifda^{c aθ-θānī} The second frog

  < ذنب ðanab Tail [of Cetus]

• Kaffaljidhmah [Al Kaff al Jidhma] (86/γ Cet) 3.47

  < الكف الجذماء al-kaf al-jaðmā´ The lepered (?) hand [reaching from the ]

• Baten Kaitos (55/ζ Cet) 3.73

  < بطن baţn belly + κήτος whale

• Deneb Algenubi [Dheneb, Deneb] (31/η Cet) 3.46

  < الذنب الجنوبي að-ðanab al-janūbiyy The southern fluke

• Schemali [Deneb Kaitos Shemali] (8/ι Cet) 3.56

  < ذنب كايتوس الشمالي ðanab kāytūs aš-šamāliyy The northern fluke of Cetus

• 91/λ Cet (or Menkar, see α Cet) 4.71

• Mira [Mira Ceti] or Collum Ceti (68/ο Cet) ~2.00 – Mira variable prototype

  < stella mīra The wondrous star

• Al Sadr al Ketus (89/π Cet)

  < صدر şadr chest + κήτος Chest of Cetus

• Tau Ceti 3.49 – nearby; has a circumstellar disk (52/τ Cet)

• Al Nitham

  < النظام an-niz̧ām The arrangement/string (of pearls/stones/stars)

• 17/ψ^{1 Cet} 4.77
• 19/ψ^{2 Cet} 5.17
• 22/ψ^{3 Cet} 5.35
• 23/ψ^{4 Cet} 5.62

Stars with Bayer designations:

82/δ Cet 4.08; 83/ε Cet 4.83; 45/θ Cet 3.60; 96/κ Cet 4.84 – nearby; 87/μ Cet 4.27; 78/ν Cet 4.87; 65/ξ¹ Cet 4.36; 73/ξ² Cet 4.30; 72/ρ Cet 4.88; 76/σ Cet 4.74; 53/χ Cet 4.66; 59/υ Cet 3.99

Stars with Flamsteed designations:

1 Cet 6.28; 2 Cet 4.55; 3 Cet 4.99; 4 Cet 6.43; 5 Cet 6.18; 6 Cet 4.89; 7 Cet 4.44; 9/BE Cet 6.39 – variable; 10 Cet 6.16; 12 Cet 5.72; 13 Cet 5.20; 14 Cet 5.94; 15 Cet 6.64; 18 Cet 6.15; 20 Cet 4.78; 21 Cet 6.15; 25 Cet 5.40; 26 Cet 6.06; 27 Cet 6.09; 28 Cet 5.58; 29 Cet 6.44; 30 Cet 5.71; 32 Cet 6.40; 33 Cet 5.97; 34 Cet 5.93; 35 Cet 6.55; 37 Cet 5.14; 38 Cet 5.70; 39 Cet 5.42; 40 Cet 6.52; 42 Cet 5.87; 43 Cet 6.50; 44 Cet 6.21; 46 Cet 4.90; 47 Cet 5.51; 48 Cet 5.11; 49 Cet 5.62; 50 Cet 5.41; 54 Cet 5.92; 56 Cet 4.92; 57 Cet 5.43; 58 Cet 6.52; 58 Cet 8.83; 60 Cet 5.42; 61 Cet 5.96; 63 Cet 5.94; 64 Cet 5.64; 66 Cet 5.65; 67 Cet 5.51; 69 Cet 5.29; 70 Cet 5.42; 71 Cet 6.34; 75 Cet 5.36; 77 Cet 5.74; 79 Cet 6.83 – has a planet; 80 Cet 5.53; 81 Cet 5.65; 84 Cet 5.72; 85 Cet 6.32; 93 Cet 5.62; 94 Cet 5.07 – has a planet; 95 Cet 5.62; 97 Cet 5.70

Other notable stars:

• Luyten 726-8 – nearby

• UV Ceti 12.57 – flare star
• BL Ceti 12.70 – variable

• YZ Ceti 12.05 – variable

Template:ConstellationsListedByPtolemy Template:ConstellationList

External links

Template:Commons

• The Deep Photographic Guide to the Constellations: Cetus (http://www.allthesky.com/constellations/cetus/)ca:Cetus

de:Walfisch (Sternbild) es:Cetus fr:Baleine (constellation) ga:An Míol Mór ko:고래자리 id:Cetus it:Cetus nl:Cetus ja:くじら座 pl:Wieloryb (gwiazdozbiór) pt:Cetus sk:Súhvezdie Veľryba fi:Valaskala th:กลุ่มดาวซีตัส