ι Serpentis, Latinized as Iota Serpentis and abbreviated Iot Ser, is a triple star[7] system in the constellation Serpens, in its head (Serpens Caput). It is approximately 190 light years from Earth.[1]
Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Serpens |
Right ascension | 15h 41m 33.05469s[1] |
Declination | 19° 40′ 13.4380″[1] |
Apparent magnitude (V) | 4.51[2] |
Characteristics | |
Evolutionary stage | main sequence |
Spectral type | B9V + A1V[3] |
B−V color index | +0.062±0.003[2] |
Astrometry | |
Radial velocity (Rv) | −17.20[4] km/s |
Proper motion (μ) | RA: -60.86[1] mas/yr Dec.: -43.69[1] mas/yr |
Parallax (π) | 17.16 ± 0.67 mas[1] |
Distance | 190 ± 7 ly (58 ± 2 pc) |
Absolute magnitude (MV) | +0.69[2] |
Orbit[5] | |
Period (P) | 8015.0±6.3 d |
Semi-major axis (a) | 0.21033±0.00047″ |
Eccentricity (e) | 0.0941±0.0028 |
Inclination (i) | 83.608±0.043° |
Longitude of the node (Ω) | 69.684±0.033° |
Periastron epoch (T) | 54,180±33 HMJD |
Argument of periastron (ω) (secondary) | 80.5±1.8° |
Details | |
A | |
Mass | 1.999[3] M☉ |
B | |
Mass | 1.984[3] M☉ |
Other designations | |
Database references | |
SIMBAD | data |
At the centre of the system is a spectroscopic binary, Iota Serpentis A and B. These are both white main sequence dwarfs and both have apparent magnitudes of +5.3. This binary has an orbital period variously reported as 11[8] or 22[5] years. First discovered as an astrometric binary, the pair have now been resolved and visual orbits have been derived.[5]
There are two visual companions, Iota Serpentis C, a 13th magnitude star 143 arcseconds away and Iota Serpentis D, a 12th magnitude star 151 arcseconds distant.