Star Constellation Facts: Auriga

Star Constellation Facts: Auriga

Auriga is a beautiful pentagonal constellation that is almost circumpolar, making it visible most of the year round in the northern hemisphere, but best seen throughout autumn and winter. “The Charioteer”, as it is also known, occupies 657 square degrees of  celestial sphere north of Orion, making it the 21st largest constellation in the night sky. It also contains the 6th brightest star in the night sky, Capella, just 42.2 light years away, as well as a number of fine star clusters, including M36, M37 and M38.

Perseus Family of Constellations

Auriga belongs to the Perseus family of constellations, along with Andromeda, Cassiopeia, Cepheus, Cetus, Lacerta, Pegasus, Perseus and Triangulum.

Mythology

Auriga is most frequently depicted as a charioteer holding the reins of a chariot in his right hand while carrying a she-goat and two kids on his left arm. Of the several myths associated with Auriga, the most celebrated story concerns Erichthonius, a King of Athens and the son of the god Hephaestus, who was raised by Athena and taught many skills, including the art of taming, then harnessing four horses to a single chariot, in imitation of the Sun God’s four-horse chariot. This impressed Zeus so much that he found a place for Erichthonius amongst the stars, and later tradition came to acknowledge Erichthonius as the inventor of the quadriga, which is a special chariot drawn by four horses.

However, a simpler variation on the chariot theme in the mythology of Auriga has it that the lame god Hephaestus, built the chariot for himself to enable him to travel without difficulty whenever he so desired.

Principal Stars

Star Constellation Facts: AurigaAuriga is a fairly bright constellation, and five of its stars are second magnitude or brighter, including Capella, the sixth brightness star in the night sky, which has a visual magnitude of 0.08. In the northern skies, just Vega in the constellation Lyra, and Arcturus in Boötes are more luminous, although The “Goat Star”, as Auriga is also known, is actually a multiple system with a binary pair of stars in close orbit, while a pair of smaller red dwarfs orbit them around 10,000 AU away.

The Capella multiple system also forms part of the The Hyades Stream, a big grouping of moving stars that follow a trajectory close to that of the Hyades open star cluster in Taurus. In classical depictions, Capella forms “The Charioteer’s” left shoulder, and it represents the goat that suckled Zeus, Amalthea.

Others stars of interest include Menkalinan (Beta Aurigae), a triple star system 85 light years distant; Mahasim (Theta Aurigae), a double star about 173 light years from Earth; Almaaz (Epsilon Aurigae), an eclipsing binary star; and Sadatoni (Zeta Aurigae), another eclipsing binary star 790 light years away.

Deep Sky Objects

M36 (NGC 1960) is a open star clusters in the southern part of the constellation containing at least 60 stars, estimated to be only 25 million years old. It is about 4,100 light-years away, and approximately 14 light-years in diameter. M37 (NGC 2099) is the brightest open star cluster in Auriga, 4,511 light-years away and containing around 500 stars roughly 400 million years old.  M38 is the third of these fine star clusters, 4,200 light-years away, and containing around 100 stars of about magnitude 10 and lower. The cluster is about 220 million years old, with its brightest stars forming a prominent oblique cross, or Greek letter Pi.

Meteor Showers

Two meteor showers are connected with Auriga, the first being the Alpha Aurigids, a minor and unreliable shower that occurs primarily in the month of September, with the comet Kiess (C/1911 N1) as the source. However, intervals between showers can extend over many years, with showers observed only in 1935, (the year of its discovery), and then only again in the years 1986, 1994, 2007. The second more reliable shower meteor shower is the Delta Aurigids, which can be seen from September 22 to October 23 with the maximum occurring between Oct 6 and Oct 15.