Auriga (The Charioteer) & Capella Guide
Auriga IAU constellation (657 sq deg, rank 21): February northern pentagon led by zero-magnitude Capella (+0.08) and open clusters M36, M37, and M38.
Sky Navigation & Astrophysical Context
Auriga forms a commanding pentagon across 657 square degrees of the northern winter Milky Way directly north of Taurus and Orion. Its northwestern vertex is crowned by Capella (Alpha Aurigae, V = +0.08), the sixth-brightest star in the night sky and the brightest star north of declination +40°—a quadruple system dominated by two yellow G-type giant stars (G8 III and G0 III) orbiting every 104 days at a distance of 13.1 parsecs.
Immediately southwest of Capella lies a tight right-triangle asterism known since antiquity as 'The Kids' (Haedi), formed by Almaaz (Epsilon Aurigae, an extraordinary eclipsing binary whose 2-year eclipse repeats every 27.1 years), Sadatoni (Zeta Aurigae, a K4 II + B5 V eclipsing supergiant system), and Mahasim companion Eta Aurigae (+3.18). The southern apex of the Auriga pentagon is shared historically with Beta Tauri (Elnath).
Because the Galactic Anti-Center lies along the southern Auriga–Taurus border, sweeping the interior and southeastern edge of the pentagon with binoculars reveals a chain of three bright Messier open clusters—Messier 38 (the Starfish Cluster), Messier 36 (the Pinwheel Cluster), and Messier 37, the richest and finest open cluster in the region with over 500 resolved stars around a central orange giant.
Equatorial Center Position & Transit Altitude
Auriga is centered near Right Ascension 06h 04m 12s, Declination +42° 01′ 48″ (The Charioteer).
Practical Star-Hopping & Observing Tips
- Identify brilliant yellow Capella high overhead on winter evenings and trace the five-sided polygon through Menkalinan (Beta Aurigae), Theta Aurigae, Elnath, and Iota Aurigae.
- Sweep a 7° diagonal line from Theta Aurigae toward Elnath with 10×50 binoculars to pick up open clusters M37, M36, and M38 in succession.
- Observe the Flaming Star Nebula (IC 405) around the runaway O9.5 V star AE Aurigae using a wide-field telescope and UHC/H-beta filtration.
Notable Celestial Objects in & Near Auriga
| Object | Family | Classification | RA (J2000) | Dec (J2000) | Min. Instrument |
|---|---|---|---|---|---|
| Capella (Alpha Aurigae Giant Binary) | stars | Spectroscopic & interferometric binary of two G-type giant stars (+ M-dwarf pair) | 05h 16m 41.36s | +45° 59′ 52.8″ | Naked eye |
| Pleiades (Messier 45 Open Cluster) | open-clusters | Open star cluster with dusty reflection nebulosity | 03h 47m 00.00s | +24° 07′ 00.0″ | Naked eye; best in 7×50 or 10×50 binoculars |
| Crab Nebula (Messier 1 Supernova Remnant) | supernova-remnants | Pulsar wind nebula (plerion) and core-collapse supernova remnant | 05h 34m 31.94s | +22° 00′ 52.2″ | 70–100 mm telescope under dark skies (10×50 binoculars from dark sites) |
| Pinwheel Cluster (Messier 36 / NGC 1960) | open-clusters | Young open star cluster | 05h 36m 11.00s | +34° 08′ 27.0″ | 7×50 binoculars |
| Messier 37 (NGC 2099 Salt-and-Pepper Cluster) | open-clusters | Rich open star cluster | 05h 52m 18.00s | +32° 33′ 14.0″ | 7×50 binoculars |
| Starfish Cluster (Messier 38 / NGC 1912) | open-clusters | Open star cluster | 05h 28m 41.00s | +35° 51′ 19.0″ | 7×50 binoculars |
Scientific Sources Cited
- IAU Official Constellation Boundaries & Designations (IAU 88 Recognized Constellations): Delporte, E. 1930, Délimitation scientifique des constellations (IAU / Cambridge University Press) — International Astronomical Union (IAU)
- SIMBAD Astronomical Database (CDS) (2026-10 release): Wenger, M., et al. 2000, A&AS, 143, 9 (The SIMBAD astronomical database) — Centre de Données astronomiques de Strasbourg