Lambda Serpentis
 Location of λ Serpentis (circled) |
|
| Observation data Epoch J2000 Equinox J2000 |
|
|---|---|
| Constellation | Serpens |
| Right ascension | 15h 46m 26.614s[1] |
| Declination | +07° 21′ 11.04″[1] |
| Apparent magnitude (V) | 4.43[2] |
| Characteristics | |
| Spectral type | G0 V[3] |
| U−B color index | +0.11[2] |
| B−V color index | +0.60[2] |
| Variable type | Suspected |
| Astrometry | |
| Radial velocity (Rv) | −66.4[4] km/s |
| Proper motion (μ) | RA: -224.00 ± 0.29[1] mas/yr Dec.: -70.64 ± 0.27[1] mas/yr |
| Parallax (π) | 82.48 ± 0.32[1] mas |
| Distance | 39.5 ± 0.2 ly (12.12 ± 0.05 pc) |
| Absolute magnitude (MV) | 4.07 |
| Details | |
| Mass | 1.14[5] M☉ |
| Radius | 1.060 ± 0.152[6] R☉ |
| Luminosity | 1.94[5] L☉ |
| Surface gravity (log g) | 4.09[7] cgs |
| Temperature | 5,884 ± 4.4[8] K |
| Metallicity [Fe/H] | −0.03[7] dex |
| Rotational velocity (v sin i) | 3[9] km/s |
| Age | 3.8–6.7[10] Gyr |
| Other designations | |
Lambda Serpentis (λ Ser, λ Serpentis) is a star in the constellation Serpens, in its head (Serpens Caput). It has an apparent visual magnitude of 4.43,[2] making it visible to the naked eye. Based upon parallax measurements from the Hipparcos satellite, this star lies at a distance of about 39.5 light-years (12.1 parsecs) from Earth.[1] This star is larger and more massive than the Sun, although it has a similar stellar classification.[3] It is shining with nearly double the Sun's luminosity and this energy is being radiated from the star's outer atmosphere at an effective temperature of 5,884 K.[8]
Lambda Serpentis is moving toward the Solar System with a radial velocity of 66.4 km s−1.[4] In about 166,000 years, this system will make its closest approach of the Sun at a distance of 7.371 ± 0.258 light-years (2.260 ± 0.079 parsecs), before moving away thereafter.[11]
Hunt for substellar objects
A periodicity of 1837 days (5.03 years) was suspected by Morbey & Griffith (1987),[12] but it is probably bound to stellar activity. However, McDonald Observatory team has set limits to the presence of one or more planets[12] around Lambda Serpentis with masses between 0.16 and 2 Jupiter masses and average separations spanning between 0.05 and 5.2 Astronomical Units.
See also
References
- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 Lua error in package.lua at line 80: module 'strict' not found. Vizier catalog entry
- ↑ 2.0 2.1 2.2 2.3 Lua error in package.lua at line 80: module 'strict' not found.
- ↑ 3.0 3.1 3.2 Lua error in package.lua at line 80: module 'strict' not found.
- ↑ 4.0 4.1 Lua error in package.lua at line 80: module 'strict' not found.
- ↑ 5.0 5.1 Lua error in package.lua at line 80: module 'strict' not found.
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
- ↑ 7.0 7.1 Lua error in package.lua at line 80: module 'strict' not found.
- ↑ 8.0 8.1 Lua error in package.lua at line 80: module 'strict' not found.
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
- ↑ 12.0 12.1 Lua error in package.lua at line 80: module 'strict' not found.
Further reading
- Lua error in package.lua at line 80: module 'strict' not found.
