Mu2 Octantis
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Octans |
| μ2 Oct A | |
| Right ascension | 20h 41m 44.102s |
| Declination | −75° 21′ 02.88″ |
| Apparent magnitude (V) | +6.481±0.007 |
| μ2 Oct B | |
| Right ascension | 20h 41m 45.5181s |
| Declination | −75° 20′ 47.047″ |
| Apparent magnitude (V) | +7.153±0.011 |
| Characteristics | |
| μ2 Oct A | |
| Spectral type | G1V |
| U−B color index | +0.26 |
| B−V color index | +0.62 |
| μ2 Oct B | |
| Spectral type | G1V |
| Astrometry | |
| μ2 Oct A | |
| Radial velocity (Rv) | −10.90±0.2 km/s |
| Proper motion (μ) | RA: 156.404 mas/yr Dec.: −162.214 mas/yr |
| Parallax (π) | 25.0327±0.0205 mas |
| Distance | 130.3 ± 0.1 ly (39.95 ± 0.03 pc) |
| Absolute magnitude (MV) | 3.28 |
| μ2 Oct B | |
| Radial velocity (Rv) | −10.94±0.15 km/s |
| Proper motion (μ) | RA: +163.531 mas/yr Dec.: −171.346 mas/yr |
| Parallax (π) | 25.0379 ± 0.0167 mas |
| Distance | 130.27 ± 0.09 ly (39.94 ± 0.03 pc) |
| Orbit | |
| Semi-major axis (a) | 932 AU |
| Details | |
| μ2 Oct A | |
| Mass | 1.330±0.013 M☉ |
| Radius | 1.730+0.044 −0.039 R☉ |
| Luminosity | 3.73 L☉ |
| Surface gravity (log g) | 4.24±0.03 cgs |
| Temperature | 6,059±52 K |
| Metallicity [Fe/H] | +0.216±0.009 dex |
| Rotation | 26±3 days |
| Rotational velocity (v sin i) | 1.45 km/s |
| Age | 3.50+0.65 −0.27 Gyr |
| μ2 Oct B | |
| Mass | 1.190+0.017 −0.018 M☉ |
| Radius | 1.190+0.034 −0.010 R☉ |
| Metallicity [Fe/H] | +0.267±0.009 dex |
| Age | 2.10+1.03 −0.34 Gyr |
| Other designations | |
| μ2 Oct, CCDM J20417-7521 | |
| μ2 Oct A: CD−75°1173, HD 196067, HIP 102125, HR 7864, SAO 257836, 2MASS J20414409-7521029 | |
| μ2 Oct B: CD−75°1174, HD 196068, HIP 102128, SAO 257837, 2MASS J20414550-7520471 | |
| Database references | |
| A | |
| SIMBAD | data |
| Exoplanet Archive | data |
| Database references | |
| B | |
| SIMBAD | data |
Mu2 Octantis (μ2 Oct) is a binary star system in the constellation Octans, whose primary and secondary stars have apparent magnitudes of +6.481 and 7.153, respectively. Based on parallax measurements, it lies 130.3 light-years away.
The two stars, HD 196067 and HD 196068 (also named μ2 Oct A and μ2 Oct B), are separated at 17 arcseconds in the sky, corresponding to 740 astronomical units (AU). The semimajor axis of the stars' orbit is 932 AU.
Component A is a G-dwarf star with 1.33 and 1.73 times of the Sun's mass and radius, respectively. Component B also a G-type main-sequence star with a radius 1.19 times larger than the Sun. Their effective temperatures are similar. HD 196068 has a higher metallicity than its companion, the reasons for this are uncertain.