The Reticulum constellation contains five stars with confirmed planets and one named star — Tupi (HD 23079). The brightest star in the constellation is Alpha Reticuli, with an apparent magnitude of 3.33.
There are two notable deep sky objects in Reticulum — the barred spiral galaxy NGC 1559 and NGC 1313, yet there are no Messier objects and no meteor showers associated with the constellation.
History and Mythology Of The Reticulum Constellation
The constellation of Reticulum was created by Isaac Habrecht II, who included it on his celestial globe in 1621 and named it Rhombus. However, the French astronomer Nicolas Louis de Lacaille renamed it to le Réticule Rhomboide in the 18th century to commemorate the reticle in his telescope, which he used to measure star positions during his trip to the Cape of Good Hope in the early 1750s. The name was later Latinized to Reticulum in his star catalogue Coelum Australe Stelliferum.
Reticulum was officially recognized during the First General Assembly of the International Astronomical Union in 1922.
Location Of The Reticulum Constellation
The Reticulum Constellation is one of the smallest constellations in the night sky, landing 82nd in size out of the 88 modern constellations. It occupies an area of 114 square degrees. It is located in the first quadrant of the southern hemisphere (SQ1) and can be seen at latitudes between +23° and -90°.
Its right ascension is 4h and is declination is −60°. It is best seen at 9pm during the month of January. It cannot be seen from north of the 30th parallel north.
The neighboring constellations to Reticulum are Dorado, Horologium and Hydrus and it belongs to the Lacaille family of constellations, along with Antlia, Caelum, Circinus, Fornax, Horologium, Mensa, Microscopium, Norma, Octans, Pictor, Sculptor, and Telescopium.
Notable Stars
Alpha Reticuli
Alpha Reticuli is the brightest star in the constellation and has an apparent magnitude of 3.315. It is halfway between the giant and bright giant stage of evolution and has the stellar classification of G8 II-III. Its mass is three times the mass of the Sun and its radius is 13 times that of the Sun. It is also a known X-ray source and is believed to be about 330 million years old. It is located around 161.6 light years away from the Solar System.
CCDM J04144-6228B is a 12th magnitude companion to Alpha Reticuli and is separated from it by 48 arc seconds.
Beta Reticuli
Beta Reticuli is a triple star system with an apparent magnitude of 3.84. The primary component in the system is an orange giant with the stellar classification K0IV SB and the whole system is located around 100 light years away from us.
Delta Reticuli
Delta Reticuli is a red giant with the stellar classification of M2 III and an apparent magnitude of 4.56. It is located around 530 light years away from the Sun.
Epsilon Reticuli
Epsilon Reticuli is a double star that consists of an orange subgiant and a white dwarf and is located around 59.5 light years away from Earth. The primary component has the stellar classification of K2 IV and an apparent magnitude of 4.44, and the companion belongs to the stellar class D and has a visual magnitude of 12.5. The stars share a common proper motion through space and it is thought they probably form a binary system.
In December 2000, a planet was found orbiting the primary star with a period of 418 days. It is thought to have a minimum mass of 1.17 times that of Jupiter.
Gamma Reticuli
Gamma Reticuli is a red giant star that belongs to the stellar class M4III and has an apparent magnitude of 4.48. It is located around 490 light years away from the Solar System.
Iota Reticuli
Iota Reticuli is an orange giant with the stellar classification K4III and an apparent magnitude of 4.97. It is located around 331 light years away from the Sun.
Kappa Reticuli
Kappa Reticuli is a binary star with a primary component of a yellow-white subgiant with the stellar classification of F5IV-V. It has an apparent magnitude of 4.71 and is located around 70 light years away from Earth. It is thought to be about 1.8 billion years old.
Zeta Reticuli
Zeta Reticuli is a wide binary system composed of two yellow G-class stars, both of which have a visual magnitude of 5.22 and are located around 39 light years from the Solar System. Both of the stars are also solar analogs, meaning they share similar characteristics with the Sun, and they both belong to the Zeta Herculis Moving Group of stars that share a common origin. The two stars are separated by 309.2 seconds of arc and appear as a close pair to the unaided eye in good viewing conditions.
Zeta-1 Reticuli is a yellow main sequence star with the stellar classification of G3-5V and Zeta-2 Reticuli is a yellow dwarf with the stellar classification of G2V.
Eta Reticuli
Eta Reticuli is a yellow giant star with the stellar classification of G7III and an apparent magnitude of 5.24. It is located around 380 light years away from Earth.
Theta Reticuli
Theta Reticuli is a double star that is located around 462 light years away from the Sun and has an apparent magnitude of 5.88. The primary component is a blue-white star halfway between the subgiant and giant stage of evolution.
R Reticuli
R Reticuli, also known as S Reticuli, is a Mira variable, meaning it is a strikingly red pulsating variable star that will expel its outer envelope as a planetary nebula within a few million years and become a white dwarf. It is located around 5,000 light years away from the Sun and has an apparent magnitude of 9.23.
HD 23079
HD 23079 is a main sequence star that belongs to the spectral class F8 or G0 and has an apparent magnitude of 7.1. It is located around 113.5 light years away from the Solar System and is thought to be around 6.53 billion years old. It is both larger and more massive than the Sun.
In October 2001, a giant planet was discovered orbiting the star with a period of 730.6 days. The planet has a mass at least 2.45 times that of Jupiter.
HD 23127
HD 23127 is a yellow dwarf with the stellar classification G2V and an apparent magnitude of 8.58. It is located around 320 light years away from Earth and is thought to be around seven billion years old. Its mass is 1.13 times that of the Sun and has twice the Sun’s metal content.
On February 9, 2007, a planet with an orbital period of 1,214 days was discovered orbiting HD 23127. It is 37 percent more massive than Jupiter.
HD 25171
HD 25171 is a yellow-white main sequence star with the stellar classification F8 V and an apparent magnitude of 7.79. It is located around 179 light years away from the Solar System and can be seen in a small telescope. It is slightly larger and more massive than the Sun and has 189 percent of the Sun’s luminosity. This main sequence star is also around four billion years old.
There is a plant orbiting the star with a period of 1,845 days. The planet has a mass 0.95 times that of Jupiter.
HD 27894
HD 27894 is an orange dwarf star with the stellar classification of K2 V and an apparent magnitude of 9.42. It is located around 143 light years away from Earth. In 2005, a planet was discovered in the star’s orbit with a period of 17.991 days. It has a mass 0.62 times that of Jupiter.
Deep Sky Objects
NGC 1559
NGC 1559 is a barred spiral galaxy that has an apparent magnitude of 11. It is classified as a Seyfert galaxy and is about seven times smaller than the Milky Way, with massive spiral arms. It contains regions of intense star formation and the galaxy’s disc and bar are a source of strong radio emissions. The galaxy is located around 50 million light years away from us.
Three supernovae have been discovered in NGC 1559 — SN 1984J in 1984, SN 1986L in 1986 and SN 2005df in 2005.
Topsy Turvy Galaxy
The Topsy Turvy Galaxy, also known as NGC 1313, is a barred spiral galaxy that was discovered by the Scottish astronomer James Dunlop on September 27, 1826. It is located around 15 million light years away from the Milky Way, near the galaxy NGC 1309 in Eridanus constellation.
The Topsy Turvy Galaxy is also a starburst galaxy and spans about 50,000 light years. It is notable because it is very uneven in shape and its axis of rotation is not located in its center.
Images:
- 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/
- Reticulum 1 – https://starregistration.net/constellations/reticulum-constellation.html
- Reticulum 2 – https://in-the-sky.org/data/constellation.php?id=71
- NGC 1559 – https://en.wikipedia.org/wiki/NGC_1559
- Topsy Turvy Galaxy – https://www.eso.org/public/news/eso0643/