On the nights till December 22, 2023, look ahead to the moon, as it should move above the constellation Cetus the Whale. The moon will close to the tail of Cetus, cross above the physique after which seem close to the whale’s head. So the moon could be your information to Cetus on these nights. What else is close by? Solely our solar system’s largest planet, and the brightest “star” within the night sky, Jupiter.
Cetus the Whale doesn’t have Jupiter’s brightness. But it surely’s noteworthy because the 4th-largest of the 88 constellations. Solely Ursa Major the Nice Bear, Virgo the Maiden and Hydra the Water Snake are larger. Additionally, Cetus lies in part of the evening sky that represents a celestial sea. You’ll discover it under Pisces the Fish and Eridanus the River. Different water-themed constellation inhabit this area of the sky as nicely.
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The mythology of Cetus
In Greek mythology, Cetus was a fearsome sea monster. Cetus practically ate Andromeda the Chained Woman earlier than Perseus the Hero arrived and saved the day, slaying Cetus. And relying on the parable you learn, Cetus both meets its destiny on the sword of Perseus or by turning to stone after viewing the severed head of Medusa.
The celebrities of Cetus the Whale
The brightest star within the head of Cetus is Menkar, shining at magnitude 2.54, but it surely’s the second brightest star within the physique Cetus and in addition goes by the title Alpha Ceti. It’s positioned about 250 light-years away.
The star that marks the place the whale’s head joins its neck is the three.47-magnitude star Kaffaljidhma, or Gamma Ceti. Transferring towards the physique of the whale is Delta Ceti at magnitude 4.08. Delta can be helpful later for locating Cetus’ one distinguished galaxy.
The following star within the physique of the whale is the well-known Mira the Great. Mira, or Omicron Ceti, is a well-liked variable star, which is one which adjustments in brightness. This long-period variable star can get as brilliant as magnitude 2 and as dim as magnitude 10. While you evaluate it to the opposite stars in Cetus, how brilliant does Mira look tonight? One other curious characteristic of Mira is that it’s dashing by way of space at 290,000 miles per hour (466,000 km/h). This immense pace and the truth that Mira is nearing the top of its life and ejecting materials means the fantastic star sports activities a tail that stretches for an unimaginable 13 light-years.
The brightest star in Cetus goes by three totally different names: Beta Ceti, Diphda and Deneb Kaitos. This star shines at magnitude 2, lies within the tail of the beast and is 96 light-years away.
Lastly, the star Earendel is probably the most distant star ever detected. As a matter of reality – it’s so distant – it emitted the sunshine we now see some 12.9 billion years in the past.
Galaxies in Cetus the Whale
The one Messier object in Cetus is the Squid galaxy or M77. It lies only a degree east-southeast of the star Delta Ceti. M77 shines at magnitude 8.8 from 47 million light-years away. The face-on spiral galaxy has an lively galactic nucleus and a noticeably brilliant heart. These with massive telescopes could possibly catch one other galaxy between Delta Ceti and M77. The magnitude -10.6 galaxy NGC 1055 resides there.
By the best way, M77 is mostly the primary object to search out if you happen to’re doing a Messier Marathon in spring. That’s as a result of it slips away quick within the western night twilight that point of yr.
Nebulae in Cetus the Whale
One notable planetary nebula lies six levels north of the brightest star Diphda, or Deneb Kaitos. NGC 246 has a magnitude of 8. The nebula has a bubble or ring-shaped look and is 1,600 million light-years away.
Planetary nebulae come into being when stars puff off materials towards the top of their lives. Mira will finally create one other planetary nebula in Cetus when it ends its life and ejects its remaining gasoline. As a becoming moniker for a star that has given up the ghost, NGC 246 additionally bears the nickname of the Skull nebula.
Backside line: Cetus the Whale is a large constellation that swims in a sea of stars close to constellations named for a river and fish. Its most notable star is Mira the Great. The moon – and Jupiter – are close to Cetus from December 19-23, 2023.
