[Pic]

Abbreviation:

Aur

English name:

Charioteer

Coordinates

see Stellar data

Particulars:

• Spectroscopical binaries alpha Aur, beta Aur
• Eclipsing binaries epsilon Aur (period: 27 years), zeta Aur (period: 2 2/3 years)
• Double stars theta Aur, omega Aur
• Planetary nebula NGC(*) 2149
• Diffuse nebulae I 405, I 410
• Star clusters M 36, M 37, M 38 , NGC 2281, NGC 1907, NGC 1664
• Meteor Showers: Aurigids, Alpha Aurigids, Delta Aurigids, Zeta Aurigids

General:

A quite large constellation of the northern hemisphere, located between DECL=55 degrees and DECL=28 degrees, RA=7h 30m and RA=4h 40m. There is no star gamma Aur. The reason for this is that the star, which would be listed as gamma Aur is shared with the constellation Taurus (its lying exactly on the boundary) and is listed as beta Tau.
As the Milky Way runs through this constellation it is quite a pleasure to view this part of the sky.

Stars and other objects

The yellow giant alpha Aur, called Capella, is the 6th brightest star in the sky (0.08 mag). It is also a spectroscopic binary consisting of a G5III and a G0III. They revolve each other every 104 days.
Menkalinen, beta Aur, is also a spectroscopic binary. Within just four days the stars complete their revolution much faster than those of alpha Aur. Since they are eclipsing each other the brightness of beta Aur seems to vary.
The eclipsing binary epsilon Aur has an extradinary long period; every 27.1 years the brightness varies from 3.0 mag down to 3.8 mag as the brighter component is then eclipsed by the darker companion. This eclipse lasts a full year (the last eclipse took place in 1983). Caculations show that the dark component of epsilon Aur has about 10 -12 solar masses. Because of its small size it is a good candidate for a black hole; unfortunately this conflicts with the observed lost of brightness during the eclipse. According to studies of Wilson and Cameron the solution is a ring of obsuring material which surrounds the black hole. (There is still doubt that the companion is a black hole; a star which a 10 times smaller brightness would fit the model, too.)
Another eclipsing binary is zeta Aur; a K4 bright giant and a B8 main sequence star revolve each other every 2 2/3 years.
The double omega Aur can be viewed with small telescopes; it consists of a 5th mag and a 8th mag companion.
Telescopes with an aperture of at least 100mm and a high magnification are required to split the tight double theta Aur. An A0psi star of 2.62 mag is accompanied by a star of 7th mag.
The planetary nebula NGC(*) 2149 (the asterix indicates that this object can be found in the NGC supplementary catalogs of J.L.E. Dreyer) appears as a small oval ring of 10th mag.
The diffuse nebula I 405 is also called Flaming Star.
I 410 consists of a cluster with an nebulosity attached.
There a several open clusters in this constellations.
About 60 members belong to M36. Its a good object for the use of binoculars. A beautiful group of stars is M38 showing an oval shape. The richest of these three Messier objects is M37. It contains about 150 stars with magnitudes of 12.5 and brighter and about 500 in total. Detailed information about all three Messier objects can be found in the Messier database.
The meteor shower of the Aurigids is generally observable between January, 31st, and February, 23rd. This shower is known for its bright fireballs.
From August, 25th, till September 6th, the shower of the Alpha Aurigids is active. Although the annual maximum is about 9 meteors, outbursts of up to 30 were observed in 1935 and 1986.
The Delta Aurigids may be observed between September 22nd and Ovctober 23rd. The maximum of this shower occurs around October 6th to October 15th.
Please refer to Gary Kronk's database about meteor showers for details about all four showers.

Mythological Background:

Auriga may represent the sea god Poseidon, dring his chariot drawn by sea horses.