| |
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Lupus |
| Right ascension | 15h24m 45.00855s[1] |
| Declination | −39° 42′ 36.9524″[1] |
| Apparent magnitude (V) | 5.37[2] (5.37 + 10.90)[3] |
| Characteristics | |
| Spectral type | A0p Si[4] |
| B−V color index | −0.11[2] |
| Astrometry | |
| Radial velocity (Rv) | −7.6±2.8[5] km/s |
| Proper motion (μ) | RA: −26.10[1] mas/yr Dec.: −54.77[1] mas/yr |
| Parallax (π) | 8.02 ± 0.62 mas[1] |
| Distance | 410 ± 30 ly (125 ± 10 pc) |
| Absolute magnitude (MV) | −0.10[6] |
| Details | |
| υ Lup A | |
| Luminosity | 113[7] L☉ |
| Temperature | 10,049[7] K |
| Rotational velocity (v sin i) | 0[8] km/s |
| Other designations | |
υ Lup, CD−39° 9827, HD 136933, HIP 75439, HR 5719, SAO 206597.[9] | |
| Database references | |
| SIMBAD | data |
Upsilon Lupi, Latinized from υ Lupi, is a star system in the southern constellationofLupus. It is faintly visible to the naked eye with an apparent visual magnitude of 5.37.[2] Based upon an annual parallax shift of 8.02[1] mas as seen from Earth, it is located around 410 light years from the Sun. The two components of Upsilon Lupi share a common proper motion through space and most likely form a wide binary star system.[10] As of 1945, the pair had an angular separation of 1.50 arc seconds along a position angle of 40°.[3]
The brighter member, component A, is a chemically peculiar Ap star with a stellar classification of A0p Si,[4] where the 'Si' suffix indicates an abnormal abundance of silicon in the star's photosphere. A magnetic field has been detected with a quadratic field strengthof(764.7±311.3)×10−4 T.[11] The star is radiating 113 times the solar luminosity from its outer atmosphere at an effective temperature of 10,049 K.[7]
The magnitude 10.9 companion star, component B, has a visual magnitude of 10.90.[3] It may be the source of the X-ray emission detected coming from these coordinates.[12]
