Observation data Epoch J2000.0 Equinox J2000.0 | |
---|---|
Constellation | Andromeda |
Right ascension | 23h 34m 37.53652s [2] |
Declination | +40° 14′ 11.1795″ [2] |
Apparent magnitude (V) | 5.55 [3] |
Characteristics | |
Spectral type | A1 III, [4] A1 Va, [5] or kA1hA3mA0.5 Va+. [6] |
U−B color index | 0.08 |
B−V color index | 0.096±0.005 [3] |
Variable type | δ Sct [7] |
Astrometry | |
Radial velocity (Rv) | 13.1±0.6 [3] km/s |
Proper motion (μ) | RA: -18.165 mas/yr Dec.: −46.183 [2] mas/yr |
Parallax (π) | 12.9406 ± 0.0973 mas [2] |
Distance | 252 ± 2 ly (77.3 ± 0.6 pc) |
Absolute magnitude (MV) | +1.16±0.16 [8] |
Details [4] | |
Mass | 2.7 M☉ |
Luminosity | 27 L☉ |
Surface gravity (log g) | 3.90±0.03 [8] cgs |
Temperature | 9,225 K |
Rotational velocity (v sin i) | 105 [8] km/s |
Age | 130 Myr |
Other designations | |
Database references | |
SIMBAD | data |
15 Andromedae, abbreviated 15 And, is a single, [10] variable star [7] in the northern constellation of Andromeda. 15 Andromedae is the Flamsteed designation, while its variable star designation is V340 And. [9] Its apparent visual magnitude is 5.55, [3] which indicates it is faintly visible to the naked eye. Its estimated distance from the Earth is 252 light years, and it is moving further away with a heliocentric radial velocity of 13 km/s. [3]
Depending on the source, this star has been classified as a giant star with a stellar classification of A1 III, [4] an A-type main-sequence star with a class of A1 Va, [5] or a Lambda Boötis star with a class of kA1hA3mA0.5 Va+. [6] It is a Delta Scuti variable that changes in brightness by 0.03 magnitude. [7] Two variability cycles, with periods 0.0403 and 0.0449 days, have been observed, a common feature for Lambda Boötis stars. [11] The star is around 130 [4] million years old and has a high rotation rate, showing a projected rotational velocity of 105 km/s. [8] It has 2.7 times the mass of the Sun and is radiating 27 times the Sun's luminosity from its photosphere at an effective temperature of 9,225 K. [4]
This system has an excess emission of infrared radiation that suggests the presence of an orbiting disk of dust at a distance of around 50 AU from the host star. [4]
2 Andromedae, abbreviated 2 And, is a binary star system in the northern constellation of Andromeda. 2 Andromedae is the Flamsteed designation. It is a faint star system but visible to the naked eye with a combined apparent visual magnitude of 5.09. Based upon an annual parallax shift of 7.7 mas, it is located 420 light years away. The binary nature of the star was discovered by American astronomer Sherburne Wesley Burnham at Lick Observatory in 1889. The pair orbit each other over a period of 74 years with a high eccentricity of 0.8.
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.
9 Andromedae, abbreviated 9 And by convention, is a variable binary star system in the northern constellation Andromeda. 9 Andromedae is the Flamsteed designation, while it bears the variable star designation AN Andromedae, or AN And. The maximum apparent visual magnitude of the system is 5.98, which places it near the lower limit of visibility to the human eye. Based upon an annual parallax shift of 7.1 mas, it is located 460 light years from the Earth.
Xi Aurigae, Latinized from ξ Aurigae, is the Bayer designation for a single, white-hued star in the northern constellation of Auriga. This star was once considered part of the constellation of Camelopardalis and held the Flamsteed designation 32 Camelopardalis. It is visible to the naked eye with an apparent visual magnitude of +5.0. The measured annual parallax shift of this star is 13.37 ± 0.17 mas, which corresponds to a physical distance of 244 light-years with a 3 light-year margin of error. At that distance, the visual magnitude of the star is diminished by an extinction of 0.108 due to interstellar dust.
Theta Boötis, Latinized from θ Boötis, is a star in the northern constellation of Boötes the herdsman, forming a corner of the upraised left hand of this asterism. It has the traditional name Asellus Primus and the Flamsteed designation 23 Boötis. Faintly visible to the naked eye, this star has a yellow-white hue with an apparent visual magnitude of 4.05. It is located at a distance of 47.2 light years from the Sun based on parallax, but is drifting closer with a radial velocity of −10.6 km/s.
47 Boötis is a binary star system in the northern constellation of Boötes, located 261 light years away from the Sun. It has the Bayer designation k Boötis; 47 Boötis is the Flamsteed designation. The system is visible to the naked eye as a faint, white-hued star with a combined apparent visual magnitude of 5.58. It is moving closer to the Earth with a heliocentric radial velocity of −13 km/s.
50 Cancri is a single star in the zodiac constellation of Cancer, located 183 light years away from the Sun. It has the Bayer designation A2 Cancri; 50 Cancri is the Flamsteed designation. It is faintly visible to the naked eye as a white-hued star with an apparent visual magnitude of 5.89. The star is moving away from the Earth with a heliocentric radial velocity of 23 km/s, having come to within 118 light-years some 1.2 million years ago.
HD 179791 is suspected variable star in the equatorial constellation of Aquila. It is a challenge to see with the naked eye even under good viewing conditions, having an apparent visual magnitude of 6.48. The distance to HD 179791 can be estimated from its annual parallax shift of 5.3 mas, which yields a value of 616 light years. It is moving further from the Earth with a heliocentric radial velocity of +16 km/s. Astrometric measurements of the star show changes in motion that may indicate it is a member of a close binary system.
HD 16955, also known as HR 803, is a double or multiple star. With an apparent visual magnitude of 6.376, is lies at or below the nominal limit for visibility with a typical naked eye. The measured annual parallax shift is 9.59 milliarcseconds, which yields an estimated distance of around 340 light years. The star is moving closer to the Sun with a heliocentric radial velocity of around -10 km/s.
HD 128333 or CH Boötis is an irregular variable star in the northern constellation of Boötes. It is currently on the asymptotic giant branch of the HR diagram.
HD 134064 is a binary star system in the northern constellation of Boötes. It is faintly visible to the naked eye with a combined apparent visual magnitude of 6.03. This system is located at a distance of 247 light years from the Sun based on parallax measurements, but is drifting closer with a radial velocity of –7.0 km/s.
Tau2 Serpentis, Latinized from τ2 Serpentis, is a star in the constellation of Serpens, located approximately 480 light-years from the Sun. It is a challenge to view with the naked eye, having an apparent visual magnitude of 6.22. The star is drifting closer with a radial velocity of −19 km/s.
R Boötis is a variable star in the northern constellation of Boötes. Typically the star is too faint to be readily visible to the naked eye, with a brightness that fluctuates between apparent visual magnitudes of 9.98. The distance to this star is approximately 2,150 light years based on parallax measurements. It is drifting closer with a radial velocity of about −58 km/s.
HD 211575 is a star in the constellation Aquarius in between "Gamma Aquarii", "Pi Aquarii" and "Sadalmelik". It is a member of the corona of the Ursa Major moving group.
Phi2 Ceti, Latinized from φ2 Ceti), is a star located in the equatorial constellation of Cetus. φ2 Ceti is also known as 19 Cet, and HD 4813. Based upon parallax measurements, it is located about 51 light years away. It has an apparent visual magnitude of +5.19, making it bright enough to be seen with the naked eye. The star is drifting further away with a radial velocity of +8 km/s.
29 Cygni is a single star in the northern constellation of Cygnus. It is dimly visible to the naked eye as a white-hued star with an apparent visual magnitude of 4.93. The distance to 29 Cyg, as estimated from an annual parallax shift of 24.5 mas, is 133 light years. The star is moving closer to the Earth with a heliocentric radial velocity of −17 km/s. It is a member of the 30–50 million year old Argus Association of co-moving stars.
AZ Phoenicis is a variable star in the constellation of Phoenix. It has an average visual apparent magnitude of 6.47, so it is at the limit of naked eye visibility. From parallax measurements by the Gaia spacecraft, it is located at a distance of 322 light-years from Earth. Its absolute magnitude is calculated at 1.65.
HD 74423 is a heartbeat binary star and one component pulsates on only one hemisphere. This is caused by tidal interaction with its partner. The star is located in the Volans constellation.
HD 66920, also known as HR 3171, is a solitary, white hued star located in the southern circumpolar constellation Volans, the flying fish. It has an apparent magnitude of 6.33, placing it near the limit for naked eye visibility. Based on parallax measurements from the Gaia spacecraft, the star is estimated to be 428 light years distant. It appears to be receding from the Solar System, having a heliocentric radial velocity of 23.8 km/s. Pauzen et al. (2001) listed it as a λ Boötis star, but is now considered a non member.
HD 218108, also known as HR 8786, is a solitary, white hued star located in the southern circumpolar constellation Octans. It has an apparent magnitude of 6.11, making it faintly visible to the naked eye under ideal conditions. Based on parallax measurements from Gaia DR3, the object is estimated to be 247 light years away. It appears to be approaching the Solar System with a fairly constrained radial velocity of −7 km/s. Paunzen et al. (2001) lists it as a λ Boötis star with a weak magnesium line.