HD 41004
Visual binary star in the constellation Pictor / From Wikipedia, the free encyclopedia
HD 41004 is a visual binary[4] star system in the southern constellation of Pictor. It is too faint to be visible to the naked eye, having a combined apparent visual magnitude of 8.65.[2] The two components have a magnitude difference of 3.7, and share a common proper motion[4] with an angular separation of 0.30″, as of 2018.[3] The distance to this system is approximately 136 light years based on parallax.[1] It is drifting further away from the Sun with a radial velocity of +42.5 km/s, having come to within 44.5 ly some 831,000 years ago.[2]
Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Pictor |
Right ascension | 05h 59m 49.64736s[1] |
Declination | −48° 14′ 22.8058″[1] |
Apparent magnitude (V) | 8.65[2] (8.82 + 12.51)[3] |
Characteristics | |
Spectral type | K1V + M2V[4] |
B−V color index | 0.887±0.013[2] |
Astrometry | |
Radial velocity (Rv) | +42.5±0.5[2] km/s |
Proper motion (μ) | RA: −41.520±0.485[1] mas/yr Dec.: +59.652±0.556[1] mas/yr |
Parallax (π) | 24.0437 ± 0.2635 mas[1] |
Distance | 136 ± 1 ly (41.6 ± 0.5 pc) |
Absolute magnitude (MV) | 5.60[2] |
Details[5] | |
A | |
Mass | 0.89±0.07 M☉ |
Radius | 1.04+0.02 −0.03[1] R☉ |
Luminosity | 0.629±0.008[1] L☉ |
Surface gravity (log g) | 4.34±0.11 cgs |
Temperature | 5,255±52 K |
Metallicity [Fe/H] | 0.15±0.03 dex |
Rotational velocity (v sin i) | 1.0±1.2[6] km/s |
B | |
Mass | 0.4[7] M☉ |
Other designations | |
Database references | |
SIMBAD | data |
The primary, component A, is a K-type main-sequence star with a stellar classification of K1V[4] and a visual magnitude of 8.82.[3] Torres et al. (2006) classed it as a K1IV star,[6] suggesting it is a subgiant star that is evolving off the main sequence. It has 89%[4] of the mass of the Sun and 104%[1] of the Sun's radius. The star is radiating 63%[1] of the Sun's luminosity from its photosphere at an effective temperature of 5,255 K.[4] Its smaller companion, designated component B, is a red dwarf with spectral type M2V[4] and apparent magnitude 12.33. It has a projected separation of 23 AU from the primary.[4]