Carina constellation is located in the southern sky and was originally part of the much larger constellation Argo Navis, along with constellations Puppis and Vela, which was first catalogued by the Greek astronomer Ptolemy in the 2nd century. The name Carina means “the keel”, as in the keel of a ship, in Latin, while Puppis means “the stern” and Vela means “the sails”.
In the 18th century, French astronomer Nicolas Louis de Lacaille divided Argo Navis into the three smaller constellations, which were then added to the official list of the modern constellations in the early 20th century.
The constellation is also home to a number of deep sky objects, including the Wishing Well Cluster, the Diamond Cluster and the Theta Carinae Cluster, but it is not home to any Messier objects. There are two meteor showers associated with the constellation: the Alpha Carinids and the Eta Carinids. The Eta Carinids peaks around January 21 each year.
History and Mythology
Carina used to be part of the constellation of Argo Navis, along with constellations Puppis and Vela. While Carina itself isn’t associated with any myths, Argo Navis represented the ship on which Jason and the Argonauts sailed to Colchis to get the Golden Fleece.
The ship was named after its creator Argus, who built it under the orders of Athena, using timber from Mount Pelion. Carina represents the main body of Argo Navis and the star Canopus marks the blade on one of the ship’s steering oars.
Argo Navis originally occupied a vast area of space between the constellations Canis Major and Crux. Due to the massive size of Argo Navis and the sheer number of stars that required separate designation, Nicolas Louis de Lacaille divided Argo into three sections in 1763, including Carina.
The constellation of Carina is the 34th largest constellation in the sky and occupies an area of 494 square degrees. It lies in the second quadrant of the southern hemisphere (SQ2) and can be seen at latitudes between +20° and -90°.
Its right ascension is 06h 02m 59.7365s–11h 20m 37.4211s and its declination is −50.7545471°–−75.6840134°. It is best seen at 9pm during the month of March.
Carina’s neighboring constellations are Centaurus, Chamaeleon, Musca, Pictor, Puppis, Vela and Volans and it belongs to the Heavenly Waters family of constellations, along with Columba, Delphinus, Equuleus, Eridanus, Piscis Austrinus, Puppis, Pyxis and Vela.
Canopus, also known as Alpha Carinae, is the brightest star in the constellation of Carina and the second brightest star in the night sky. It is an F-type bright giant with an apparent magnitude of -0.74 and an absolute magnitude of -5.53, making it 13,600 times brighter than the Sun. It is the most luminous star within about 700 light years of us.
Canopus is around 310 light years away from us. When observed from latitudes south of 37°18’, the star never sets below the horizon, yet it never rises north of 37°18’ and it cannot be observed from far-northern latitudes. The star belongs to the Scorpius-Centaurus Association, which is the nearest OB association to our solar system.
The name Canopus is a Latinised version of the Greek name Kanôbos, documented in Ptolemy’s Almagest. Canopus is also sometimes known as Suhail and the Chinese know Canopus as the Star of the Old Man.
Miaplacidus, also known as Beta Carinae, is the second brightest star in Carina and the 29th brightest star in the sky. It has an apparent magnitude of 1.67 and is an A-type subgiant, located around 111 light years away from Earth and close to IC 2448.
Miaplacidus is part of the south polar asterism, the Diamond Cross, along with Theta, Upsilon and Omega Carinae. Its name means “placid waters”, which is derived from the combination of the Arabic word for waters (miyāh) and the Latin word for placid (placidus).
Avior, also known as Epsilon Carinae, is a double star that consists of a K0 III class orange giant, one approaching the end of its life, and a hot hydrogen-fusing blue dwarf belonging to the spectral class B2 V. It is the 40th brightest star in the night sky and has an apparent magnitude of 1.86. It is located around 630 light years away from us, yet cannot be observed from many locations in the northern hemisphere.
The components that make up Avior regularly eclipse each other which causes variations in luminosity by 0.1 magnitudes. Its name was given to it in the late 1930s as it did not have a name and the Royal Air Force, who used a navigational almanac that pilots could navigate by, insisted that all stars on it have names.
Aspidiske, also known as Iota Carinae, is a rare white supergiant that belongs to the spectral type A8 Ib. It is the 68th brightest star in the sky and has an apparent magnitude of 2.21. It is located around 690 light years away from us and is part of the Flase Cross asterism with Avior and Delta and Kappa Velorum in the constellation Vela. The False Cross got its name because it is often mistaken for the Southern Cross.
Aspidiske is thought to be around 40 million years old and has a mass seven times that of the Sun and a luminosity of 4,900 times that of the Sun. Its name means “shield” in Greek, but it is also known as Turais and Scutulum, which are diminutives of the word “shield” in Arabic and Latin.
Eta Carinae is a star system composed of at least two stars with a combined brightness that is four million times the luminosity of the Sun. It is classified as a luminous blue variable (LBV) binary star and belongs to the spectral class WR pe. It is located between 7,500 and 8,000 light years away from Earth and occasionally undergoes powerful outbursts, which account for the changes in the star’s brightness. However, it is unknown what causes the outbursts. The largest star in the system has more than 100 solar masses.
Eta Carinae is a known x-ray source and was first catalogued as a fourth magnitude star by the English astronomer and physicist Edmond Halley in 1677. By 1730 it has brightened significantly and became one of the most prominent stars in Carina, but it dimmed again in 1982. In 1843, it was the second brightest star in the sky.
– A Magnificent Ending
The star is expected to explode as a supernova or hypernova in the next million years or so. In 1843, a supernova impostor event was observed in the direction of Eta Carinae, during which the star emitted almost as much visible light as a supernova explosion would have produced. However, the star remained.
Some believe that the supernova explosion of Eta Carinae will happen in our lifetime, based on the system’s similarity to that of the star that became the supernova SN 2006jc. It is thought that when Eta Carinae does explode, the event might affect Earth, since the star is only 7,500 light years away. The Earth’s atmosphere will protect the population, but the upper layers of the atmosphere, satellites, the ozone layer and any astronauts in space could be harmed.
Eta Carinae is sometimes known by its traditional names, Tseen She (“heaven’s altar” in Chinese) and Foramen. It cannot be observed north of latitude 30°N and it does not fall below the horizon south of latitude 30°S.
Theta Carinae is a blue-white main sequence dwarf belonging to the spectral class B0Vp. It has an apparent magnitude of 2.74. It is located 439 light years away from us, and lies on the northeastern end of the Diamond Cross. Theta Carinae is also the most prominent star in IC 2602, which is a an open cluster of stars in Carina that is sometimes called the Southern Pleiades because it resembles the famous Pleiades cluster.
Upsilon Carinae is a double star that consists of a white A-type supergiant and a blue-white B-type giant. They are separated by five arc seconds, around 1,623 light years away from Earth, and have apparent magnitudes of 3.01 and 6.26.
Omega Carinae is a blue-white B-type giant that has an apparent magnitude of 3.29. It is located around 370 light years away from us and is one of the stars that form the Diamond Cross.
Chi Carinae is a blue-white subgiant that is also a Beta Cephei type variable star. It has a mean apparent magnitude of 3.46, yet its brightness varies by 0.015 magnitudes with a period of 2.42 hours. It is located around 387 light years away from Earth.
PP Carinae is a blue-white B-type main sequence dwarf that is also a shell star, a Gamma Cassiopeiae type variable, which means it is a fast rotating star with a disc of gas surrounding it at the equator. It has a mean apparent magnitude of 3.30 and is located around 497 light years away from Earth.
AG Carinae is a luminous blue variable star that is believed to be undergoing the transitional evolutionary phase between an O-class supergiant and a Wolf-Rayet star. It has an absolute magnitude of -10.3 and its apparent magnitude varies between 5.7 and 9.0, making it one of the brightest stars known in the Milky Way. It is located around 6,000 light years away from us and is surrounded by a large planetary nebula.
I Carinae, also known as HD 84810, is a yellow G-type supergiant that is classified as a Cepheid variable star. Its brightness varies between magnitudes 3.28 and 4.18 with a period of 35.54 days and its mean apparent magnitude is 3.69. It is located around 1,510 light years from Earth.
V337 Carinae is a K-type bright giant that is also a variable star. It is located around 740 light years away from us and has an apparent magnitude that varies between 3.36 and 3.44.
V357 Carinae is a spectroscopic eclipsing binary star that is composed of two blue-white B-type subgiants with an orbital period of 6.75 days. They have a mean apparent magnitude of 3.43 and are located around 419 light years away from us.
V382 Carinae is a yellow G-type hypergiant that is also classified as a Cepheid variable star. Its luminosity varies from magnitude 3.84 to 4.02. It is located around 5930.90 light years away from Earth and it is 747 times the size of the Sun.
V533 Carinae is a white A-type supergiant that is classified as an Alpha Cygni type variable star. It has a mean apparent magnitude of 4.59 and is located around 4,000 light years away from Earth.
Deep Sky Objects
The Carina Nebula, also known as the Eta Carinae Nebula or NGC 3372, is one of the largest diffuse nebulae known. It surrounds the massive stars Eta Carinae and HD 93129A, as well as several open star clusters, and is brighter and four times the size of the Orion Nebula. It has an apparent magnitude of 1.0.
The nebula was discovered by the French astronomer Nicolas Louis de Lacaille in 1751-52, who observed it from the Cape of Good Hope, and it is between 6,500 and 10,000 light years away from us. It contains several O-type stars, as well as two smaller nebulae, the Homunculus Nebula and the Keyhole Nebula.
The Homunculus Nebula is an emission nebula which surrounds the star Eta Carinae. It is thought to have formed after an enormous outburst from the star, which is when Eta Carinae became the second brightest star in the night sky. Its name means “little man” in Latin.
The Keyhole Nebula is a small, dark cloud of dust and cold molecules with bright filaments of fluorescent gas that appears contrasted against the bright nebula in the background. It was named by John Herschel in the 19th century and is about seven light years in diameter.
The Carina Nebula has an interesting peanut shape, which the origin has been much theorized about. It is thought that the central star might share the same shape, or the explosion created a wave.
Theta Carinae Cluster
The Theta Carinae Cluster, also known as the Southern Pleiades, IC 2602 or Caldwell 102, is an an open cluster with an apparent magnitude of 1.9. It was first discovered by Lacaille in 1751 and is visible to the naked eye. It is located around 479 light years away from us and spans about 50 arc minutes and contains about 60 stars in total.
Most of the stars fifth magnitude or fainter. The brightest star in the cluster is Theta Carinae, a blue-white dwarf. The name for the cluster “the Southern Pleiades” was given to it because of its resemblance to the famous cluster in the constellation of Taurus.
Wishing Well Cluster
The Wishing Well Cluster, also known as NGC 3532, is an open cluster which is composed of about 150 stars. The brightest stars are of seventh magnitude and the cluster is located around 1,321 light years away from us, between the constellation Crux and the False Cross asterism. It is named the Wishing Well Cluster because in a telescope, its stars appear like silver coins twinkling at the bottom of a wishing well. It was the first object ever observed by the Hubble Space Telescope in May 1990.
The Diamond Cluster
The Diamond Cluster, also known as NGC 2516, Caldwell 96 or C96, is an open cluster that was discovered by Lacaille in 1751-52. It can be seen without binoculars in good conditions and was named after its stellar clarity. Its brightest stars are two magnitude five red giants and three binary stars.
NGC 3603 is an open cluster that was originally catalogued by John Herschel as a nebula in 1847. It has an apparent magnitude of 9.1 and is located around 20,000 light years away from Earth, in the Carina spiral arm of the Milky Way Galaxy.
The cluster contains three Wolf-Rayet stars, one of which is 200 times more massive than the Sun, and the central star, HD 97950, has an apparent magnitude of 9.03. HD 97950 is composed of four stars of the type A1-A3 and B, and five other stars.
NGC 3603 contains the densest concentration of massive stars known in the galaxy. It is also surrounded by a H II region, the most massive visible cloud of plasma and gas in the Milky Way.
NGC 3293 is an open star cluster that contains over 50 stars. It was discovered by Lacaille in the mid-18th century. The brightest star in the cluster is a magnitude 6.5 red giant and the cluster spreads across an area of 10 arc minutes.
NGC 2808 is a globular star cluster that is one of the most massive clusters in the Milky Way Galaxy. It has an apparent magnitude of 7.8 and is thought to be around 12.5 billion years old. It is composed of three different generations of stars, all formed within 200 million years of the cluster’s formation.
- The stars of Carina can barely be seen in China.
- The star Canopus was located by Chinese astronomers in the Vermilion Bird of the South.
- Polynesian peoples had no name for the constellation in particular, though they had many names for Canopus.
- By the year 4700 the south celestial pole will be in Carina, due to the precession of Earth’s axis.
- In the future, three bright stars in Carina will come within 1 degree of the southern celestial pole and take turns as the southern pole star — Omega Carinae in 5600, Upsilon Carinae in 6700 and Iota Carinae in 7900.
- There was a United States Navy Crater class cargo ship named after the constellation — USS Carina (AK-74).
Some Images created with the NightVision app – https://www.nvastro.com/nvj.html
Some Images created with the Stelvision Sky Map https://www.stelvision.com/en/sky-map/
Carina 1 – https://starregistration.net/constellations/carina-constellation.html
Carina 2 – https://in-the-sky.org/data/constellation.php?id=18
Canopus – https://earthsky.org/brightest-stars/few-know-the-second-brightest-star-canopus
Aspidiske – https://theskylive.com/sky/stars/aspidiske-iota-carinae-star
Carina Nebula – https://en.wikipedia.org/wiki/Carina_Nebula
Wishing Well Cluster – https://skyandtelescope.org/online-gallery/ngc-wishing-well-cluster/
The Diamond Cluster – https://www.astrobin.com/376234/?nc=all