Arcturus vs Capella
Neighbouring spectral types describe the pair, a K-type star for Arcturus against an M-type star for Capella. Both lie at a comparable distance from the Sun — 36.7 light-years for Arcturus and 42.8 for Capella. Seen from Earth the ranking is Arcturus first at −0.05, Capella second at +0.08. Corrected for distance, Capella outproduces Arcturus by some 1.2 times, absolute magnitudes −0.51 and −0.31.
Property comparison
| Property | Arcturus | Capella |
|---|---|---|
| Designation | 16Alp Boo | 13Alp Aur |
| Constellation | N/A | N/A |
| Spectral Class | Class K — K-type (Orange) | Class M — M-type (Red) |
| Apparent Magnitude | -0.05 | +0.08 |
| Absolute Magnitude | -0.31 | -0.51 |
| Distance | 36.7 ly | 42.8 ly |
| Mass | N/A | N/A |
| Radius | N/A | N/A |
| Temperature | N/A | N/A |
| Luminosity | N/A | N/A |
Full data for each star: Arcturus · Capella
Key differences
Key Differences
- ◆ Both are G-K giant systems among the six brightest stars in the night sky.
- ◆ Arcturus is a single K-type giant with an unusual high-velocity orbit through the Galaxy.
- ◆ Capella consists of two G-type giants orbiting each other every 104 days.
- ◆ Arcturus is slightly closer at ~36.7 light-years; Capella is ~43 light-years away.
- ◆ Arcturus is the brightest star in the northern hemisphere; Capella is the brightest in Auriga.