Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Eridanus |
Right ascension | 02h 39m 47.96544s [1] |
Declination | −42° 53′ 30.3638″ [1] |
Apparent magnitude (V) | +4.74 [2] |
Characteristics | |
Spectral type | A1 Vb [3] + M2-5V [4] + ? |
B−V color index | 0.061±0.003 [2] |
Astrometry | |
Radial velocity (Rv) | +18.0±4.2 [2] km/s |
Proper motion (μ) |
RA: +88.20
[5]
mas/
yr Dec.: −17.82 [5] mas/ yr |
Parallax (π) | 24.7076 ± 0.3930 mas [1] |
Distance | 132 ± 2
ly (40.5 ± 0.6 pc) |
Absolute magnitude (MV) | +1.76 [6] |
Details | |
Aa | |
Mass | 1.95 [7] M☉ |
Radius | 1.93 [8] R☉ |
Luminosity | 17.44 [2] L☉ |
Surface gravity (log g) | 4.40±0.14 [7] cgs |
Temperature | 9,099±309 [7] K |
Metallicity [Fe/H] | −0.06 [3] dex |
Rotational velocity (v sin i) | 167.6±1.7 [9] or 13.4±1.5 [6] km/s |
Age | 212 [7] or 30 [8] Myr |
Other designations | |
Database references | |
SIMBAD | data |
HD 16754 is a binary [11] or triple-star [8] system in the constellation Eridanus. It has the Bayer designation s Eridani; HD 16754 is the designation from the Henry Draper catalogue. The system is visible to the naked eye as a faint point of light with an apparent visual magnitude of +4.74. [2] It is located at a distance of approximately 132 light years from the Sun based on parallax, [1] and is drifting further away with a radial velocity of +18 km/s. [2] The system is a member of the Columba association of co-moving stars. [12]
This object was flagged as an astrometric binary based on proper motion measurements made from the Hipparcos spacecraft. [13] [14] Zuckerman et al. (2011) consider it a multi-star system, with a bright A-type primary plus a faint M-type companion at an angular separation of 25 ″ to the north. The astrometric companion to the primary remains unresolved. [8]
The main component is an A-type main-sequence star with a stellar classification of A1 Vb. [3] Based upon stellar models, it has an age estimated at 212 million years. [7] Consistency with its membership in the Columba association suggests a much younger age of 30 million years. [8] Earlier measurements showed a high projected rotational velocity of 168 km/s. [9] However, Ammler-von Eiff and Reiners (2012) found a much lower velocity of 13 km/s. [6]
The visible companion is a red dwarf star with a class in the range M2-5V. The system is a source of X-ray emission with a luminosity of 924×1020 W, which is most likely coming from this component and the unresolved companion. [4]
Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Eridanus |
Right ascension | 02h 39m 47.96544s [1] |
Declination | −42° 53′ 30.3638″ [1] |
Apparent magnitude (V) | +4.74 [2] |
Characteristics | |
Spectral type | A1 Vb [3] + M2-5V [4] + ? |
B−V color index | 0.061±0.003 [2] |
Astrometry | |
Radial velocity (Rv) | +18.0±4.2 [2] km/s |
Proper motion (μ) |
RA: +88.20
[5]
mas/
yr Dec.: −17.82 [5] mas/ yr |
Parallax (π) | 24.7076 ± 0.3930 mas [1] |
Distance | 132 ± 2
ly (40.5 ± 0.6 pc) |
Absolute magnitude (MV) | +1.76 [6] |
Details | |
Aa | |
Mass | 1.95 [7] M☉ |
Radius | 1.93 [8] R☉ |
Luminosity | 17.44 [2] L☉ |
Surface gravity (log g) | 4.40±0.14 [7] cgs |
Temperature | 9,099±309 [7] K |
Metallicity [Fe/H] | −0.06 [3] dex |
Rotational velocity (v sin i) | 167.6±1.7 [9] or 13.4±1.5 [6] km/s |
Age | 212 [7] or 30 [8] Myr |
Other designations | |
Database references | |
SIMBAD | data |
HD 16754 is a binary [11] or triple-star [8] system in the constellation Eridanus. It has the Bayer designation s Eridani; HD 16754 is the designation from the Henry Draper catalogue. The system is visible to the naked eye as a faint point of light with an apparent visual magnitude of +4.74. [2] It is located at a distance of approximately 132 light years from the Sun based on parallax, [1] and is drifting further away with a radial velocity of +18 km/s. [2] The system is a member of the Columba association of co-moving stars. [12]
This object was flagged as an astrometric binary based on proper motion measurements made from the Hipparcos spacecraft. [13] [14] Zuckerman et al. (2011) consider it a multi-star system, with a bright A-type primary plus a faint M-type companion at an angular separation of 25 ″ to the north. The astrometric companion to the primary remains unresolved. [8]
The main component is an A-type main-sequence star with a stellar classification of A1 Vb. [3] Based upon stellar models, it has an age estimated at 212 million years. [7] Consistency with its membership in the Columba association suggests a much younger age of 30 million years. [8] Earlier measurements showed a high projected rotational velocity of 168 km/s. [9] However, Ammler-von Eiff and Reiners (2012) found a much lower velocity of 13 km/s. [6]
The visible companion is a red dwarf star with a class in the range M2-5V. The system is a source of X-ray emission with a luminosity of 924×1020 W, which is most likely coming from this component and the unresolved companion. [4]