The Taurus constellation is one of the 12 constellations of the zodiac and it was first catalogued by the Greek astronomer Claudius Ptolemy in the 2nd century CE. However, its history actually dates back to the Bronze Age. In Greek mythology, the constellation is associated with Zeus, who transformed himself into a bull to get close to Europa and abduct her.
This constellation is known for its three brightest stars Aldebaran, Elnath and Alcyone. It is also well known for Messier 45, also called Pleiades, and Hyades, which are the two nearest open star clusters to Earth. Altogether, Taurus contains 17 formally named stars, as well as two Messier objects.
History and Mythology Of The Taurus Constellation
Taurus and its location have been known since at least the Early Bronze Age, when it marked the Sun’s location during the spring equinox. It is most commonly associated with the bull in different cultures, particularly in Greek and Egyptian mythologies. Carvings and depictions of Taurus have been found in a cave painting at Lascaux, dating back to 15,000 BC, too.
Taurus is associated with Zeus in Greek mythology, who transformed himself into a bull to get close to Europa, the beautiful daughter of the Phoenician King Agenor, to abduct her.
Zeus mingled with the king’s herd and, because he was the most handsome bull there, he got Europa’s attention. When she sat on his back, he rose and headed for the sea. Zeus carried Europa all the way to the island of Crete, where he revealed his true identity.
In another version of the story, Europa was also seduced by Zeus who was then transformed into a bull when the two were nearly caught by Hera.
Location Of The Taurus Constellation
Taurus is the 17th largest constellation in the sky, occupying an area of 797 square degrees. It is located in the first quadrant of the northern hemisphere (NQ1) and can be seen at latitudes between +90° and -65°.
It’s right ascension is 4.9h and it’s declination is 19°. It is best visible at 9pm in the month of January. As of 2008, the Sun appears in the constellation Taurus from May 13 to June 21.
Taurus belongs to the zodiac family of constellations, along with Aries, Gemini, Cancer, Leo, Virgo, Libra, Scorpius, Sagittarius, Capricornus and Pisces. It’s neighboring constellations are Aries, Auriga, Cetus, Eridanus, Gemini, Orion and Perseus.
Notable Stars
There are a number of notable stars in the constellation of Taurus. Its three brightest stars are Aldebaran, Elnath and Alcyone.
Aldebaran
Aldebaran, also known as Alpha Tauri, is the brightest star in the constellation of Taurus and the 13th brightest star in the sky. It is an orange giant with an apparent magnitude varying between 0.75 and 0.95. This star got its name, which translates as “the follower”, because it appears to follow the Pleiades cluster, the Seven Sisters, across the sky.
Aldebaran has the stellar classification K5III and is located around 65.1 light years from Earth. It is classified as a slow irregular variable, type LB. Its brightness varies by about 0.2 magnitudes. It has a diameter 44.2 times that of the Sun and is about 425 times more luminous.
This star is fairly easy to find in the sky as it lies close to the Orion constellation and the three bright stars that form Orion’s Belt point in its direction. The star also helps to find Haydes Cluster, although it is not a member of the cluster but merely lies in the same line of sight.
Elnath
Elnath, also known as Beta Tauri, is the second brightest star in the constellation of Taurus and has a visual magnitude of 1.68. It is a giant star with the stellar classification B7III and is located around 131 light years away from us.
Elnath is 700 times more luminous than the Sun. Its name is derived from the Arabic word an-naţħ, which means “the butting,” referring to the bull’s horns.
Alcyone
Alcyone, also known as Eta Tauri, is the third brightest star in Taurus constellation and the brightest member of the Pleiades cluster. It has an apparent magnitude of 2.873 and is approximately 370 light years distant from the Sun.
Alcyone is actually an eclipsing binary system composed of two stars separated by 0.031 seconds of arc. Alcyone A is the main star and is a blue-white giant belonging to the spectral class B7IIIe. It has a visual magnitude of 2.87 and has ten times the radius of the Sun. It is also around 2,400 times more luminous. Alcyone A is a rapid rotator, too, with a projected rotational velocity of 215 km/s.
Alcyone A has three companions – Alcyone B, Alcyone C, and Alcyone D. The Alcyone B and Alcyone C objects are 8th magnitude white dwarfs of the spectral type A, and Alcyone D is a yellow-white dwarf belonging to the spectral class F.
Zeta Tauri
Zeta Tauri is a spectroscopic binary star with the stellar classification B2 IIIpe. It is located around 440 light years away from us and has a visual magnitude of 3.010.
The primary star is has a mass 11 times that of the Sun and 5 to 6 times the Sun’s radius. It is a rapid rotator with a projected rotational velocity of 125 km/s. The companion star is slightly less massive than the Sun. Together, the two components have an orbital period of roughly 133 days.
Theta Tauri
Theta Tauri is a binary star that is in the Haydes cluster. The two components in the system, Theta-1 Tauri and Theta-2 Tauri, are separated by 5.62 arc minutes. Theta-1 Tauri is 154.4 light years distant from the solar system and Theta-2 Tauri is 150.4 light years away.
Theta-1 Tauri is an orange, class K giant and Theta-2 Tauri is a white giant belonging to the spectral class A7 III. The Theta-1 Tauri star is the dimmer of the two with a visual magnitude of 3.84 and, while the other has an apparent magnitude of 3.40.
Pectus Tauri
Pectus Tauri, also known as Lambda Tauri, is a triple star in Taurus constellation. Its name is derived from Latin and means “the bull’s chest”. It has an overall visual magnitude of 3.47 and is approximately 480 light years away from us.
Pectus Tauri’s main component is an inner pair of stars, known as Lambda Tauri AB, which orbit each other every 3.95 days and form an eclipsing binary star system. It has a combined apparent magnitude varies from 3.37 to 3.91 and belongs to the spectral class B3 V.
Lambda Tauri AB has a mass more than seven times the Sun and a radius more than 6.4 times the Sun. It is also about 5,801 times more luminous than the Sun and is a rapid rotator, with a projected rotational velocity of 85 km/s.
The secondary star is also a rapid rotator with a velocity of 76 km/s. It is a subgiant of the spectral type A4 IV and is around 1.9 times more massive than our Sun and 128 times more luminous. The third star is about half as massive as the Sun and orbits the inner pair with a period of 33.025 days.
Ain (Oculus Borealis)
Ain, also known as Oculus Borealis and Epsilon Tauri, is an orange giant with the stellar classification K0 III. It has an apparent magnitude of 3.53 and is approximately 147 light years away from us. The names Ain and Oculus Borealis both mean “eye”.
Epsilon Tauri is a member of the Haydes cluster and is thought to be about 625 million years old. It was the first planet discovered in an open cluster and it is still the only known planet in the Haydes cluster.
Hyadum I
Hyadum I, also known as Gamma Tauri, is another member of the Haydes cluster. It is a giant star belonging to the spectral class G8III. It is located around 154 light years distant from the Sun and has an apparent magnitude of 3.654. Its radius is 13.4 times the radius of the Sun and it is 85 times more luminous that the Sun.
Gamma Tauri is thought to be between 430 and 530 million years old. Its name means “First Hyad” in Latin.
Ushakaron
Ushakaron, also known as Xi Tauri, is a triple star system consisting of three blue-white main sequence dwarfs of the spectral type B. Two of the three stars are in a close orbit, and they revolve around each other once every 7.15 days, while the pair orbits the third star in the system every 145 days.
Xi Tauri has a magnitude that ranges from 3.70 to 3.79 and it is around 222 light years in distance from the Sun.
Delta Tauri
Delta Tauri is found in Haydes cluster and consists of three star systems. Delta-1 Tauri is the main star system with a combined apparent magnitude of 3.77. It is approximately 153 light years distant from the Sun. The primary component in Delta-1 Tauri is an orange giant with the stellar classification K0 III. It is 74 times brighter than the Sun and has 11.6 times the Sun’s radius.
Delta-2 Tauri is a main sequence dwarf with the stellar classification A7V, that has a visual magnitude of 4.80 and is approximately 146 light years in distance.
Delta-3 Tauri is also a triple star system with an apparent magnitude of 4.30. It is approximately 148 light years distant from the solar system. The primary component in Delta-2 Tauri is a white subgiant star of the spectral type A2IV.
Kappa Tauri
Kappa Tauri is also found in the Haydes cluster and is a binary star consisting of two A-type stars. One is a subgiant with a visual magnitude of 4.21 and the other is a dwarf star with a magnitude of 5.27. Kappa Tauri is approximately 148 light years distant from the Sun.
Upsilon Tauri
Upsilon Tauri belongs to the Haydes cluster and is another triple star in Taurus. It has an apparent magnitude of 4.28 and is approximately 155 light years away from us.
Upsilon Tauri has a main sequence dwarf of the spectral type A as the primary component, which varies in brightness from magnitude 4.28 to 4.31 every 3.56 hours. It is a spectroscopic binary star, with components separated by 0.02 arc seconds.
The third component of Upsilon Tauri is a 12th magnitude star separated by 110 arc seconds from the main pair.
119 Tauri
119 Tauri has a diameter 600 times that of the Sun and is one of the largest stars known. It is also one of the reddest stars known in the night sky with a colour index of 2.07. It is a red giant with the stellar classification M2Iab-Ib and an apparent magnitude of 4.32. This massive star is also around 1,802 light years away from Earth.
119 Tauri lies near the ecliptic and can be occulted by the Moon. Very occasionally it can also be occulted by planets, too.
Rho Tauri
Rho Tauri, belonging to the spectral class A8V, is a white main sequence star that belongs to the Haydes cluster. It has a mass that is 1.88 times that of the Sun and has a visual magnitude of 4.65. It is around 152 light years away from us.
Rho Tauri is a fast rotator with a projected rotational velocity of 117 km/s and an estimated rotation period of 488.5 days.
111 Tauri
111 Tauri is a double star. The primary star is of the spectral type F8 V and the secondary star belongs to the spectral class K5 V.
Together, the components have an apparent magnitude of 5.1149 and are located 46.9 light years away form us. They are also known as an x-ray source.
Omicron Tauri
Omicron Tauri is a giant, binary star with the stellar classification G6 III Fe-1. It has an apparent magnitude of 3.61 and is approximately 212 light years distant from Earth.
It rotates once every 533 days and has 18 times the solar radius and three times the solar mass. In terms of brighness, it is also 155 times more luminous that the Sun.
T Tauri
T Tauri is a variable star that was discovered by the English astronomer John Russell Hind in October 1852. It is located near Epsilon Tauri, which is a member of the Haydes cluster, but around 420 light years behind it.
The variables of T Tauri are pre-main sequence stars that belong to the spectral classes F, G, K and M. They are much more luminous than main sequence stars that have the same mass, purely because they have larger radii.
T Tauri has at least three stars, although only one of them can be seen at optical wavelengths, while the other two are visible in the infrared. They are located near the reflection nebula NGC 1555 and have an apparent magnitude of 10.27 and are thought to be 600 light years distant from Earth.
RV Tauri
RV Tauri is a yellow supergiant with the stellar classification G2eIA-M2Ia. It has a varying magnitude from 9.5 to 13.5 over a period of 78.5 days.
RV Tauri is thought to be nearing the final stages of its life. It will soon expel its outer layers to become a planetary nebula and contract into a white dwarf. It is around 7,100 light years away from us.
HD 37124
HD 37124 is a yellow dwarf star of the spectral type G4V. It has an apparent magnitude of 7.68 and is about 110 light years away from us. In 2005, it was confirmed that three extrasolar planets were orbiting HD 37124.
Atlas
Atlas, also known as 27 Tauri, – not to be confused by the moon of Saturn with the same name – is a triple star that was named after the Titan Atlas, father of the Pleiades. It has a visual magnitude of 3.62 and is approximately 381 light years distant from the Sun.
Atlas A is the primary component in the system and is a blue-white giant with the stellar classification B8 III. It has a visual magnitude of 4.1 and 5.6, while the companion, Atlas B, has an apparent magnitude of 6.8.
Electra
Electra, also known as 17 Tauri, is a blue-white giant with the stellar classification B6 IIIe. It is the third brightest star in the Pleiades cluster. Electra has an apparent magnitude of 3.705 and is approximately 600 light years distant from Earth.
Electra is a rapid rotator with a projected rotational velocity of 181 km/s. It is occasionally occulted by the Moon and less frequently by planets.
Maia
Maia, also known as 20 Tauri, is a blue giant belonging to the spectral class B8III. It belongs to the Maia Nebula (NGC 1432), found in the Pleiades cluster.
Maia has a visual magnitude of 3.871 and is located approximately 360 light years away from us. It has four times the mass of our Sun and 5.5 times its radius. It is also 660 times more luminous than the Sun.
Merope
Merope, also known as 23 Tauri, is a blue-white subgiant star belonging to the spectral class B6IVe. It is around 630 times more luminous than the Sun, with a visual magnitude of 4.113, and is located approximately 360 light years away from us. It has 4.5 solar masses and four times solar radii. Marope is surrounded by the Merope Nebula.
Taygeta
Taygeta, also known as 19 Tauri, is a triple star system that is located around 440 light years away from the solar system. It has an apparent magnitude of 4.30.
Taygeta A is the primary component and is a spectroscopic binary star — a blue-white subgiant with the stellar classification B6IV. The two stars have magnitudes of 4.6 and 6.1 and are separated by 0.012 seconds of arc, completing an orbit around each other every 1,313 days.
Pleione
Pleione, also known as 28 Tauri or BU Tauri, is a binary star in the Pleiades cluster with the stellar classification B8Ivpe. It has a visual magnitude of 5.048 and is approximately 392 light years distant. Unfortunately, Pleione is difficult to see with the naked eye because it lies close to the brighter Atlas.
Pleione is about 190 times brighter than the Sun. It was named after the mythological Pleione, the daughter of Tethys and Oceanus and mother of the Hyas, Hyades and Pleiades.
Calaeno
Calaeno, also known as Celeno or 16 Tauri, is a blue-white subgiant with the stellar classification B7IV. It has an apparent magnitude of 5.448 and is located around 430 light years away from the solar system.
Calaeno has a radius of four times that of the Sun and has a projected rotational velocity of 185 km/s. It is the most difficult one of the seven Pleiades sisters to find and it can only be seen without binoculars under good conditions and clear skies.
Asterope
Asterope, also known as 21 and 22 Tauri, are two stars that are separated by 0.04° and both lie about 440 light years away from us. Located in the Pleiades cluster, 21 Tauri is a sequence dwarf star with the stellar classification B8 V and 22 Tauri is also a main sequence dwarf with the spectral classification A0Vn.
21 Tauri has a magnitude of 5.76 and 22 Tauri has a visual magnitude of 6.43.
Deep Sky Objects
There are a number of deep sky objects in constellation Taurus, including Messier objects and nebulae. Take a look below.
The Crab Nebula
The Crab Nebula, also known as Messier 1, is a supernova remnant. Messier 1 was first discovered by the English doctor and astronomer John Bevis in 1731 and was the first astronomical object to be entered in Messier’s catalogue in 1758.
Messier 1 is a pulsar wind nebula, meaning it is a nebula that is powered by the pulsar wind of a pulsar, usually found within shells of supernova remnants.
The Crab Nebula is has an apparent magnitude of 8.4. It is about 11 light years in diameter and expanding at the rate of 1,500 km per second. It is thought to be around 6,500 light years away from the Sun.
Crab Pulsar is a neutron star, a remnant of the supernova SN 1054, in the center of the nebula. It was first identified in 1968.
The Pleiades
The Pleiades, also known as Messier 45, is an open star cluster that consists of hot, luminous B-class stars most of which have formed in the last 100 million years. It is one of the easiest clusters to find in the sky because it is so bright and, therefore, one of the most well known.
The Pleiades cluster has an apparent magnitude of 1.6 and is located between 390 and 460 light years away form the Solar System. The nine brightest stars in the cluster were named after the Pleiades – the Seven Sisters in Greek mythology – Alcyone, Celaeno, Electra, Maia (mother of the god Hermes), Merope (wife of Sisyphus), Sterope, Taygeta – and their parents, the sea nymph Pleione and the titan Atlas.
Messier 45 will exist for another 250 million years or so, after which the gravitational interactions with nearby objects will cause the stars to disperse. The cluster is known in many different cultures and was thought to be first found in the Bronze Age.
The Hyades Cluster
The Hyades Cluster, also known as Caldwell 41, Melotte 25 or Collinder 50, is an open cluster that contains hundreds of stars. It is thought to be about 625 million years old and is the nearest open star cluster to the Sun and therefore the most studied one.
The brightest stars in Hyades Cluster are Gamma, Delta, Epsilon and Theta Tauri and they form a V shape with the brightest star in Taurus, Aldebaran. Aldebaran is not of the cluster, but lies in the same line of sight. It is actually much closer to use than Hyades Cluster.
Gamma, Delta, Epsilon and Theta Tauri form the bull’s head and together give Hyades Cluster an apparent magnitude of 0.5. They are around 153 light years away from us.
Hind’s Variable Nebula
Hind’s Variable Nebula, also known as NGC 1555, is a variable nebula that is also a reflection nebula. It varies in luminosity and lies next to the star T Tauri, where it is illuminated by it’s light. It was first discovered by John Russell Hind on October 11, 1852.
NGC 1410 and NGC 1409
NGC 1409 and NGC 1410 are a set of colliding galaxies and are connected by a pipeline of gas spanning over 20,000 light years. Because of this, there are a lot of stars formed in NGC 1410. One day, the two galaxies will merge into one thanks to their gravitational bond.
Together, these galaxies have an apparent magnitude of 15.4 and are 300 million light years away from the Sun.
Crystal Ball Nebula
The Crystal Ball Nebula, also known as NGC 1514, is a large planetary nebula with an apparent magnitude of 9.43. It is thought to be surrounding a close binary star with an orbital period of up to 10 days. It was first discovered by William Herschel in November 1790.
NGC 1746
NGC 1746 is an asterism that has a visual magnitude of 6.1. It was discovered by Heinrich Louis d’Arrest in 1863.
Merope Nebula
Merope Nebula, also known as NGC 1435, is a diffuse reflection nebula. It surrounds the star Merope and is located in the Pleiades star cluster. It is illuminated by the star’s light and has an apparent magnitude of 13.0.
Approximately 440 light years distant from the solar system, NGC 1435 was discovered by the German astronomer Wilhelm Tempel.
NGC 1647
NGC 1647 is an open star cluster with an apparent magnitude of 6.4. It is located between the bull’s horns.
NGC 1817
NGC 1817 is another open star cluster with an apparent magnitude of 7.7. It was discovered by William Herschel on February 19, 1784.
NGC 1807
NGC 1807 is also an open star cluster. It has an apparent magnitude of 7.0 and was discovered by John Herschel on January 25, 1832.
Extra Facts
- Babylonian astronomers called the Taurus constellation MUL.APIN, or “The Heavenly Bull”.
- In Buddhism, legends hold that Gautama Buddha was born when the full moon was in Vaisakha, or Taurus.
- Buddha’s birthday is celebrated with the Wesak Festival, or Vesākha, which occurs on the first or second full moon when the Sun is in Taurus.
- Taurus became an important object of worship among the Druids. Their Tauric religious festival was held while the Sun passed through the constellation.
- Among the arctic people known as the Inuit, the constellation is called Sakiattiat and the Hyades is Nanurjuk, with the latter representing the spirit of the polar bear.
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/
- Taurus 1 – https://starregistration.net/constellations/taurus-constellation.html
- Aldebaran – http://www.astronomytrek.com/star-facts-aldebaran/
- Taurus 2 – https://www.thoughtco.com/taurus-constellation-4177764
- Taurus 3 – http://www.seasky.org/constellations/constellation-taurus.html
- Elnath – http://astropixels.com/stars/Elnath-01.html
- Alcyone – https://nineplanets.org/alcyone/
- Atlas – https://www.star-facts.com/atlas/
- Merope – https://en.wikipedia.org/wiki/Merope_(star)
- The Crab Nebula – https://en.wikipedia.org/wiki/Crab_Nebula
- The Pleiades – https://en.wikipedia.org/wiki/Pleiades
- The Hyades Cluster – https://earthsky.org/favorite-star-patterns/v-shaped-hyades-star-cluster-easy-to-find