Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
---|---|
Constellation | Serpens |
Right ascension | 15h 46m 05.63636s [1] |
Declination | −01° 48′ 15.0830″ [1] |
Apparent magnitude (V) | 5.37 - 5.40 [2] |
Characteristics | |
Spectral type | B8IV/V [3] |
U−B color index | −0.40 [4] |
B−V color index | −0.05 [4] |
Variable type | SPB [5] |
Astrometry | |
Radial velocity (Rv) | 9.50±0.3 [6] km/s |
Proper motion (μ) | RA: −23.15 [1] mas/yr Dec.: −30.50 [1] mas/yr |
Parallax (π) | 7.25 ± 0.31 [1] mas |
Distance | 450 ± 20 ly (138 ± 6 pc) |
Orbit [7] | |
Period (P) | 38.927±0.004 |
Eccentricity (e) | 0.731±0.006 |
Periastron epoch (T) | 2450132.80±0.06 |
Argument of periastron (ω) (secondary) | 201.8±0.8° |
Semi-amplitude (K1) (primary) | 43.1±0.7 km/s |
Semi-amplitude(K2) (secondary) | 86±1 km/s |
Details [8] | |
Mass | 4.1 M☉ |
Luminosity | 383 L☉ |
Temperature | 13,932 K |
Rotational velocity (v sin i) | 80 km/s |
Other designations | |
Database references | |
SIMBAD | data |
25 Serpentis is a star system in the constellation of Serpens Caput. With an apparent magnitude of 5.37, it is just barely visible to the naked eye. The system is estimated to be some 450 light-years (138 parsecs) based on its parallax. [1]
25 Serpentis is a spectroscopic binary, [11] meaning that the individual components are too close to be resolved, but periodic Doppler shifts in their spectra indicate orbital motion. The system consists of a hot B-type giant and an A-type main-sequence star. The two stars orbit each other every 38.9 days, and have a very eccentric orbit, with an orbital eccentricity of 0.731. [7] The primary is a slowly pulsating B-type star, which causes the system to vary by 0.03 magnitudes; [2] for that reason it has been given the variable star designation PT Serpentis.
Xi Serpentis, Latinized from ξ Serpentis, is a triple star system in the Serpens Cauda (tail) section of the equatorial constellation Serpens. Based upon an annual parallax shift of 30.98 mas as seen from Earth, it is located 105.3 light years from the Sun. The star system is visible to the naked eye with a base apparent visual magnitude of +3.54. It is moving closer to the Sun and will make perihelion passage at a distance of 27 ly (8.2 pc) in around 690,000 years.
Omicron Serpentis is a solitary star in the Serpens Cauda (tail) section of the equatorial constellation Serpens. Based upon an annual parallax shift of 18.83 mas as seen from Earth, it is located around 173 light years from the Sun. The star is visible to the naked eye with a base apparent visual magnitude of +4.26.
Chi Aquarii, Latinized from χ Aquarii, is the Bayer designation of a star in the equatorial constellation of Aquarius. The distance to this star, based upon parallax measurements with a 7% margin of error, is roughly 610 light-years. It is visible to the naked eye with an apparent visual magnitude of +5.06.
28 Andromedae is a Delta Scuti variable star in the constellation Andromeda. 28 Andromedae is the Flamsteed designation. It also bears the variable star name GN Andromedae. Its apparent magnitude is 5.214, varying by less than 0.1 magnitudes.
15 Arietis is a single variable star in the northern constellation of Aries. 15 Arietis is the Flamsteed designation; it also bears the variable star designation AV Arietis. It has an apparent visual magnitude of 5.74, which is just bright enough to be visible to the naked eye from dark suburban skies. An annual parallax shift of 5.84 mas corresponds to a physical distance of approximately 560 light-years from Earth. At that distance, the star's brightness is reduced by 0.33 in magnitude because of extinction from interstellar gas and dust.
9 Aurigae is a star system in Auriga (constellation). It has an apparent magnitude of about 5, making it visible to the naked eye in many suburban skies. Parallax estimates made by the Hipparcos spacecraft put it at about 85.7 light-years from the solar system.
14 Aurigae is a quadruple star system located 269 light years away from the Sun in the zodiac constellation of Auriga. It has the variable star designation KW Aurigae, whereas 14 Aurigae is the Flamsteed designation. It is visible to the naked eye as a faint, white-hued star with a combined apparent visual magnitude of 5.01. The system is moving closer to the Sun with a heliocentric radial velocity of −9 km/s.
26 Aurigae is a binary star system in the northern constellation of Auriga. It is visible to the naked eye as a faint star with an apparent visual magnitude of 5.41.
Iota Canis Majoris, Latinized from ι Canis Majoris, is a solitary variable supergiant star in the southern constellation of Canis Major. It is visible to the naked eye with an apparent visual magnitude that varies between +4.36 and +4.40. The distance to this star is approximately 3,100 light years based on parallax measurements. It is drifting further away with a radial velocity of +41.2 km/s.
2 Centauri is a single star in the southern constellation of Centaurus, located approximately 183 light-years from Earth. It has the Bayer designation g Centauri; 2 Centauri is the Flamsteed designation. This object is visible to the naked eye as faint, red-hued star with an apparent visual magnitude of 4.19. It is moving away from the Earth with a heliocentric radial velocity of +41 km/s. The star is a member of the HD 1614 supercluster.
Y Carinae is a Classical Cepheid variable, a type of variable star, in the constellation Carina. Its apparent magnitude varies from 7.53 to 8.48.
Iota Herculis is a fourth-magnitude variable star system in the constellation Hercules, consisting of at least four stars all about 139 parsecs away. The brightest is a β Cephei variable, a pulsating star.
Phi Draconis is a fourth-magnitude variable star in the constellation Draco. It has the Flamsteed designation 43 Draconis. It is also a triple star system where the brightest component is a chemically peculiar Ap star.
1 Geminorum is a star in the constellation Gemini. Its apparent magnitude is 4.15.
Delta Sagittae is a binary star in the constellation of Sagitta, with an apparent magnitude of +3.68. The primary component is a red M-type bright giant, and the secondary is a B-type main-sequence star. It is approximately 430 light years from Earth, based on its Gaia Data Release 2 parallax.
Omicron1 Orionis is a binary star in the northeastern corner of the constellation Orion. It is visible to the naked eye with an apparent visual magnitude of 4.7. Based upon an annual parallax shift of 5.01±0.71 mas, it is located approximately 650 light years from the Sun. At that distance, the visual magnitude of the star is diminished by an interstellar absorption factor of 0.27 due to intervening dust.
λ Pavonis, Latinized as Lambda Pavonis, is a single, variable star in the southern constellation of Pavo. It is a blue-white hued star that is faintly visible to the naked eye with an apparent visual magnitude that fluctuates around 4.22. This object is located approximately 1,400 light years from the Sun, based upon parallax. It is a member of the Scorpius-Centaurus Association.
Gamma Phoenicis is a star system in the constellation Phoenix, located around 71.63 parsecs (233.6 ly) distant.
HY Velorum is a binary star system in the southern constellation of Vela. It is a dim star but visible to the naked eye with an apparent visual magnitude of 4.83. The distance to this system, as estimated from its annual parallax shift of 7.1 mas, is 460 light years. HY Vel most likely forms a gravitationally bound pair with the magnitude 5.45 binary system KT Vel ; both are members of the IC 2391 open cluster. As of 1998, HY Vel and KT Vel had an angular separation of 76.1″ along a position angle of 311°.
W Cygni is a semi-regular variable star in the constellation Cygnus, located 570 light-years from Earth. It lies less than half a degree southeast of ρ Cygni. W Cygni is, at times, a naked-eye star but it was not given a Bayer or Flamsteed designation. It has been proposed as a binary star system with a hotter main sequence companion, but this has not been confirmed.