26 Ursae Majoris is a single[9] star in the northern circumpolar constellation of Ursa Major, located 262 light years away from the Sun.[1] It is visible to the naked eye as a faint, white-hued star with an apparent visual magnitude of 4.47.[2] The object is moving further from the Earth with a heliocentric radial velocity of +22 km/s.[5]
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Ursa Major |
| Right ascension | 09h 34m 49.43259s[1] |
| Declination | +52° 03′ 05.3165″[1] |
| Apparent magnitude (V) | 4.47[2] |
| Characteristics | |
| Evolutionary stage | main sequence |
| Spectral type | A0 Vn[3] |
| U−B color index | +0.00[4] |
| B−V color index | +0.027±0.013[2] |
| Astrometry | |
| Radial velocity (Rv) | +22.2±1.1[5] km/s |
| Proper motion (μ) | RA: −65.74[1] mas/yr Dec.: −37.32[1] mas/yr |
| Parallax (π) | 12.44 ± 0.19 mas[1] |
| Distance | 262 ± 4 ly (80 ± 1 pc) |
| Absolute magnitude (MV) | −0.06[2] |
| Details | |
| Mass | 2.16[6] M☉ |
| Radius | 2.2[7] R☉ |
| Luminosity | 99.2[2] L☉ |
| Surface gravity (log g) | 3.94[6] cgs |
| Temperature | 9,757±332[6] K |
| Rotational velocity (v sin i) | 165[3] km/s |
| Age | 147[6] Myr |
| Other designations | |
| Database references | |
| SIMBAD | data |
This is an A-type main-sequence star with a stellar classification of A0 Vn,[3] where the 'n' indicates "nebulous" lines in the spectrum due to rapid rotation. It has a high rate of spin with a projected rotational velocity of 165 km/s,[3] which is giving it an oblate shape with an equatorial bulge that is 8% larger than the polar radius.[10] The star is 147[6] million years old with just over double[6] the mass of the Sun and twice[7] the Sun's radius. It is radiating 99[2] times the Sun's luminosity from its photosphere at an effective temperature of 9,757 K.[6]