Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Pisces |
Right ascension | 01h 16m 55.119s [2] |
Declination | +06° 48′ 42.13″ [2] |
Apparent magnitude (V) | 8.98 [3] |
Characteristics | |
Primary | |
Evolutionary stage | Main sequence |
Spectral type | G5V [4] |
B−V color index | 0.65±0.02 [4] |
Variable type | Detached Algol + RS CVn [5] |
Secondary | |
Evolutionary stage | Main sequence |
Spectral type | K3V [4] |
B−V color index | 1.04±0.07 [4] |
Astrometry | |
Radial velocity (Rv) | 6.45±0.40 [6] km/s |
Proper motion (μ) | RA: +85.250 mas/yr [2] Dec.: +20.946 mas/yr [2] |
Parallax (π) | 14.0593 ± 0.0236 mas [2] |
Distance | 232.0 ± 0.4 ly (71.1 ± 0.1 pc) |
Absolute magnitude (MV) | 4.48±0.05 [4] |
Orbit [7] | |
Period (P) | 0.86104716 d |
Eccentricity (e) | 0.0 (assumed) |
Inclination (i) | 88.9±2.0 [4] ° |
Periastron epoch (T) | 2,448,897.4226±0.0003 HJD |
Semi-amplitude (K1) (primary) | 117.20±0.18 km/s |
Semi-amplitude (K2) (secondary) | 154.81±0.37 km/s |
Details [7] | |
Primary | |
Mass | 1.0225±0.0058 M☉ |
Radius | 1.096 R☉ |
Surface gravity (log g) | 4.340±0.018 cgs |
Temperature | 5,780±100 K |
Metallicity [Fe/H] | 0.025±0.066 [8] dex |
Rotation | 0.86 d |
Rotational velocity (v sin i) | 71.01+0.37 −0.36 km/s |
Age | 4.7 Gyr |
Secondary | |
Mass | 0.7741±0.0034 M☉ |
Radius | 0.829 R☉ |
Surface gravity (log g) | 4.478±0.019 cgs |
Temperature | 4,750±80 K |
Rotation | 0.86 d |
Rotational velocity (v sin i) | 51.66+1.25 −1.20 km/s |
Other designations | |
Database references | |
SIMBAD | data |
UV Piscium is a binary star system in the constellation of Pisces. With a peak apparent visual magnitude of 8.98, [3] it is too faint to be visible to the naked eye. This is an eclipsing binary system that decreases to magnitude 10.05 during the primary eclipse, then to magnitude 9.54 with the secondary eclipse. It is located at a distance of 232 light years from the Sun based on parallax measurements, [2] and is receding with a radial velocity of 6.5 km/s. [6] The position of this star near the ecliptic means it is subject to lunar occultation. [10]
This star was found to be variable by H. Huth in 1959. [11] He determined it to be an eclipsing binary and published the first light curve with a period of 20.67 hours. R. B. Carr in 1969 proposed this to be an Algol-type variable with a minor tidal distortion of the components, plus a large, anomalous asymmetry in the light curve. [12] D. S. Hall in 1976 grouped it among the class of short-period RS CVn binaries. [13] The following year, variable, non-thermal radio emission was detected coming from this system, the first such discovered for a short-period binary. [14]
Daniel M. Popper in 1969 found a double-lined, G-type spectrum with both components showing emission in the H and K lines. [15] In 1979, A. R. Sadik deduced the system is a detached binary and suggested a bright, hot spot may produce the observed asymmetry in the light curve. He found stellar classifications of G2V and K0IV for the primary and secondary components, respectively. [12] With improved spectra, Popper found main sequence classes of G5 and K3 for the two stars. [4] The presence of a prominence was deduced in 1992, and a flare of hydrogen alpha was observed the following year. [16]
This is a close binary system with an orbital period of 0.86 days. The orbit is circular and the components are spinning rapidly in-sync with their orbital period. This rotation rate is making both stars magnetically active, with average magnetic field strengths of 137 G and 88 G for the primary and secondary, respectively. Magnetic activity cycles appear to be causing the orbital period to oscillate with a 61 year period. [17] The primary is a G-type main-sequence star of about the same size and mass as the Sun, while the secondary is a smaller K-type main-sequence star. They are estimated to be about 4.6 billion years old. [7]
33 Piscium is a binary star system in the zodiac constellation of Pisces. It is visible to the naked eye with an apparent visual magnitude of 4.61. The distance to this system, as determined from an annual parallax shift of 25.32±0.53 mas, is about 129 light years. It is moving closer to the Sun with a heliocentric radial velocity of −6.6 km/s.
RS Canum Venaticorum is a binary star system in the northern constellation of Canes Venatici. It serves as the prototype to the class of RS Canum Venaticorum variables. The peak apparent visual magnitude of this system is below the level needed to observe it with the naked eye. It is located at a distance of approximately 443 light years from the Sun based on parallax, but is drifting closer with a net radial velocity of −14 km/s. Olin J. Eggen (1991) included this system as a member of the IC 2391 supercluster, but it was later excluded.
TX Ursae Majoris is an eclipsing binary star system in the northern circumpolar constellation of Ursa Major. With a combined apparent visual magnitude of 6.97, the system is too faint to be readily viewed with the naked eye. The pair orbit each other with a period of 3.063 days in a circular orbit, with their orbital plane aligned close to the line of sight from the Earth. During the primary eclipse, the net brightness decreases by 1.74 magnitudes, while the secondary eclipse results in a drop of just 0.07 magnitude. TX UMa is located at a distance of approximately 780 light years from the Sun based on parallax measurements, but is drifting closer with a mean radial velocity of −13 km/s.
XY Ursae Majoris is a short period binary star system in the northern circumpolar constellation of Ursa Major. It is an eclipsing binary with a baseline apparent visual magnitude of 9.50. The system is located at a distance of 221.5 light years from the Sun based on parallax measurements, but is drifting closer with a radial velocity of −10 km/s. It has a relatively high proper motion, traversing the celestial sphere at the angular rate of 0.191″·yr−1.
EQ Tauri is a triple star system in the equatorial constellation of Taurus that includes a contact eclipsing binary. The system is too faint to be viewed with the naked eye, having a baseline apparent visual magnitude of 10.5. During the primary eclipse, the brightness of the system drops to magnitude 11.03, then to 10.97 during the secondary minimum. The secondary eclipse is total. Based on parallax measurements, it is located at a distance of approximately 730 light years from the Sun.
CV Serpentis is a binary star system in the equatorial constellation of Serpens. It is a detached eclipsing binary with an orbital period of 29.7 days. The system includes a Wolf–Rayet (WR) star with the identifier WR 113. The system is located at a distance of approximately 6,700 light years from the Sun based on parallax measurements. It is a member of the Serpens OB2 association of co-moving stars.
SZ Piscium is a suspected triple star system in the equatorial constellation of Pisces. The inner pair form a double-lined spectroscopic binary with an orbital period of 3.966 days. It is a detached Algol-type eclipsing binary of the RS Canum Venaticorum class with a subgiant component. The system is too faint to be readily visible to the naked eye with a combined apparent visual magnitude of 7.18. It is located at a distance of approximately 306 light years based on parallax measurements.
BH Virginis is a binary star system in the equatorial constellation of Virgo. With a typical apparent visual magnitude of 9.6, it is too faint to be visible to the naked eye. Based on parallax measurements, it is located at a distance of approximately 488 light years from the Sun. The system is drifting closer with a net radial velocity of −23 km/s.
RW Tauri is a binary star system in the equatorial constellation of Taurus. It has the designation HD 25487 in the Henry Draper Catalogue, while RW Tauri is the variable star designation. With a peak apparent visual magnitude of 8.05, it is too faint to be visible to the naked eye. The distance to this system is approximately 940 light years based on parallax measurements.
HU Tauri is a tight binary star system in the equatorial constellation of Taurus. It is an eclipsing binary, which means that the member stars periodically eclipse each other every 2.056 days. They have a combined apparent visual magnitude of 5.85, which is bright enough to be dimly visible to the naked eye. During the primary eclipse, the magnitude drops to 6.68, while the secondary eclipse decreases the magnitude to 5.91. The distance to this system, based on parallax measurements, is approximately 414 light years.
VZ Piscium is a binary star system in the equatorial constellation of Pisces. it is located at a distance of 178 light years from the Sun based on parallax measurements, and has an apparent visual magnitude of about 10.3. This is an eclipsing binary system that undergoes shallow eclipses; the brightness decreases to magnitude 10.45 during the primary eclipse, then to magnitude 10.43 with the secondary eclipse, although as a contact binary the brightness varies continuously with no period of constant maximum brightness. The system is drifting closer with a radial velocity of approximately −4 km/s, and has a net heliocentric velocity of 144.1 km/s.
SZ Lyncis is a binary star system in the northern constellation of Lynx, abbreviated SZ Lyn. It is a variable star with an apparent visual magnitude that fluctuates around 9.58, which is too faint to be visible to the naked eye. The distance to this system is approximately 1,700 light years based on parallax measurements, and it is drifting further away with a radial velocity of 34 km/s.
ER Vulpeculae is a binary star system in the northern constellation of Vulpecula, abbreviated ER Vul. It is a variable star system with a brightness that ranges from an apparent visual magnitude of 7.27 down to 7.49, which is too faint to be visible to the naked eye. This system is located at a distance of 165 light years from the Sun based on parallax measurements. It is drifting closer with a radial velocity of −25 km/s.
VV Ursae Majoris is a binary star system in the northern circumpolar constellation of Ursa Major, abbreviated VV UMa. It is a variable star system with a brightness that cycles around an apparent visual magnitude of 10.19, making it too faint to be visible to the naked eye. The system is located at a distance of approximately 1,500 light years based on parallax measurements.
AW Ursae Majoris is a binary star system in the northern circumpolar constellation of Ursa Major, abbreviated AW UMa. It is an A-type W Ursae Majoris variable with an apparent visual magnitude of 6.83, which is near the lower limit of visibility to the naked eye. This is an eclipsing binary with the brightness dropping to magnitude 7.13 during the primary eclipse and to 7.08 with the secondary eclipse. Parallax measurements give a distance estimate of 221 light years from the Sun. It is drifting closer to the Sun with a radial velocity of approximately −17 km/s. The system has a high proper motion, traversing the celestial sphere at the rate of 0.216 arc second per annum.
DM Ursae Majoris is a binary star system in the northern circumpolar constellation of Ursa Major, abbreviated DM UMa. It is sometimes identified by the Bonner Durchmusterung catalogue designation BD +61 1211; DM UMa is the variable star designation. The system has a combined apparent visual magnitude of 9.29, which is too faint to be visible to the naked eye. Based on parallax measurements, the system is located at a distance of approximately 606 light years from the Sun, but it is drifting closer with a heliocentric radial velocity of −7 km/s.
DW Ursae Majoris is an eclipsing binary star system in the northern circumpolar constellation of Ursa Major, abbreviated DW UMa. It is a cataclysmic variable of the SX Sextanis type, consisting of a compact white dwarf that is accreting matter from an orbiting companion star. The brightness of this source ranges from an apparent visual magnitude of 13.6 down to magnitude 18, which is too faint to be viewed with the naked eye. The distance to this system is approximately 1,920 light years based on parallax measurements.
RT Persei is a variable star system in the northern constellation of Perseus, abbreviated RT Per. It is an eclipsing binary system with an orbital period of 0.84940032 d (20.386 h). At peak brightness the system has an apparent visual magnitude of 10.46, which is too faint to be viewed with the naked eye. During the eclipse of the primary this decreases to magnitude 11.74, then to magnitude 10.67 with the secondary eclipse. The distance to this system is approximately 628 light years based on parallax measurements. It is drifting closer with a heliocentric radial velocity of about −12 km/s.
DV Piscium is a triple star system in the equatorial constellation of Pisces, abbreviated DV Psc. It is an eclipsing binary variable of the RS Canum Venaticorum class. The pair have a combined apparent visual magnitude of 10.59, which is too faint to be visible with the naked eye. Based on parallax measurements, DV Piscium is located at a distance of 137.5 light years from the Sun. It is drifting closer with a radial velocity of −28 km/s.
AR Piscium is a binary star system in the northern constellation of Canes Venatici, abbreviated AR Psc. It has the Henry Draper Catalogue identifier HD 8357; AR Piscium is its variable star designation. The pair have a combined apparent visual magnitude that fluctuates around 7.24, which is too faint to be readily visible to the naked eye. Parallax measurements place it at a distance of 148 light years from the Sun. The motion of this star through the Milky Way suggests it is a member of the intermediate disc population.