Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Crater |
Right ascension | 11h 21m 26.6645s [2] |
Declination | −20° 27′ 13.619″ [2] |
Apparent magnitude (V) | 8.61/11.0 [3] |
Characteristics | |
Spectral type | K7V/M2.5Ve [4] |
U−B color index | +1.20 [5] |
B−V color index | +1.36 [5] |
Variable type | BY Dra |
Astrometry | |
A | |
Radial velocity (Rv) | −0.11 [6] km/s |
Proper motion (μ) | RA: +181.231 [6] mas/yr Dec.: −92.306 [6] mas/yr |
Parallax (π) | 76.4165 ± 0.0821 mas [6] |
Distance | 42.68 ± 0.05 ly (13.09 ± 0.01 pc) |
Absolute magnitude (MV) | +7.75 [7] |
B | |
Radial velocity (Rv) | −2.86 [8] km/s |
Proper motion (μ) | RA: +220.306 [8] mas/yr Dec.: −129.404 [8] mas/yr |
Parallax (π) | 76.3549 ± 0.0955 mas [8] |
Distance | 42.72 ± 0.05 ly (13.10 ± 0.02 pc) |
Absolute magnitude (MV) | +10.0 [7] |
Orbit [9] | |
Period (P) | 714.6 yr |
Semi-major axis (a) | 5.896″ |
Eccentricity (e) | 0.63 |
Details | |
A | |
Radius | 0.63 [6] R☉ |
Luminosity | 0.109 [6] L☉ |
Surface gravity (log g) | 4.5 [10] cgs |
Temperature | 4,162 [6] K |
Metallicity [Fe/H] | 0.04 [10] dex |
Rotational velocity (v sin i) | 4.5 [10] km/s |
B | |
Radius | 0.593 [11] [lower-alpha 1] R☉ |
Luminosity | 0.0575 [11] [lower-alpha 2] L☉ |
Temperature | 3,670 [11] K |
Age | 194±20 [12] Myr |
Other designations | |
A: LTT 4204 [13] | |
B: LTT 4205 [14] | |
Database references | |
SIMBAD | data |
A | |
B |
SZ Crateris is a binary star system in the southern constellation Crater. Both components belong to the main sequence: the primary star has a spectral classification of K5V while the secondary is a red dwarf of spectral class M0V. The radius of the primary is about 66% the radius of the Sun, while the secondary member is only about 42% of the solar radius. In 1994, the two stars were separated by 5.1 arc seconds, which is equivalent to 112.41 astronomical units. [7]
SZ Crateris is classified as a marginal BY Draconis variable, and has an optical variability cycle of 11.58 days. (The star causing the variability is unspecified.) [15] Compared to the Sun, SZ Crateris has a slightly higher proportion of elements other than hydrogen and helium. [10] Based upon gyrochronology, the estimated age of this star is under 200 million years. [12]
The SZ Crateris system is a member of the Ursa Major moving group of stars that have similar motions through space. [10] The space velocity components of this system are U = +13.86 ± 0.37, V = –3.51 ± 1.97 and W = +1.65 ± 1.53 km/s. [16] It is on an orbit through the Milky Way that has an orbital eccentricity of 0.092, which will bring it as close as 26.06 kly (7.99 kpc ) to the galactic core, and as distant as 31.31 kly (9.60 kpc). The inclination of the orbit carries the system as much as 0.352 kly (0.108 kpc) from the plane of the galactic disk. [17]
Crater is a small constellation in the southern celestial hemisphere. Its name is the latinization of the Greek krater, a type of cup used to water down wine. One of the 48 constellations listed by the second-century astronomer Ptolemy, it depicts a cup that has been associated with the god Apollo and is perched on the back of Hydra the water snake.
Gliese 570 is a quaternary star system approximately 19 light-years away. The primary star is an orange dwarf star. The other secondary stars are themselves a binary system, two red dwarfs that orbit the primary star. A brown dwarf has been confirmed to be orbiting in the system. In 1998, an extrasolar planet was thought to orbit the primary star, but it was discounted in 2000.
IM Pegasi is a variable binary star system approximately 329 light-years away in the constellation of Pegasus. With an apparent magnitude of 5.7, it is visible to the naked eye. Increased public awareness of it is due to its use as the guide star for the Gravity Probe B general relativity experiment. It was chosen for this purpose because its microwave radio emissions are observable with a large radio telescope network on the ground in such a manner that its precise position can be related by interferometry to distant quasars.
Epsilon Ursae Minoris is a binary star system in the northern circumpolar constellation of Ursa Minor. It is visible to the naked eye with a combined apparent visual magnitude of 4.19. Based upon an annual parallax shift of 10.73 mas as seen from the Earth, it is located around 300 light years from the Sun. The pair are drawing nearer to the Sun with a radial velocity of −10.57 km/s.
Zeta Andromedae is a star system in the constellation Andromeda. It is approximately 189 light-years from Earth.
42 Capricorni is a binary star system in the zodiac constellation of Capricornus. It has a combined apparent visual magnitude of 5.18, so it is faintly visible to the naked eye. Its annual parallax shift of 30.09 mas yields a distance estimate of about 108 light years; the system is moving closer to the Sun with a radial velocity of −1.2 km/s. 42 Capricorni is 0.2 degree south of the ecliptic and so is subject to lunar occultations.
Beta Crateris, Latinized from β Crateris, is a binary star system in the southern constellation of Crater. It is visible to the naked eye with an apparent visual magnitude of 4.46. Based upon an annual parallax shift of 9.59 mas as seen from Earth, it is located around 340 light years from the Sun.
11 Leonis Minoris is a binary star located 36.64 light years away from Earth, in the northern constellation of Leo Minor. It is visible to the naked eye as a dim, yellow-hued star with an apparent visual magnitude of 5.54. The system is moving away from the Earth with a heliocentric radial velocity of +14.4 km/s. It has a relatively high proper motion, traversing the celestial sphere at the rate of 0.764 arc seconds per annum.
HD 17925 is a variable star in the equatorial constellation of Eridanus. It has the Gould designation 32 G. Eridani and the variable star designation EP Eri. The star has a yellow-orange hue and is dimly visible to the naked eye in good seeing conditions with an apparent visual magnitude that varies from 6.03 down to 6.08. It is located nearby at a distance of 34 light years from the Sun based on parallax, and is drifting further away with a radial velocity of +18 km/s. It is a likely member of the Local Association of nearby, co-moving stars. The spectrum shows a strong abundance of lithium, indicating that it is young star. This likely makes its point of origin the nearby Scorpio–Centaurus Complex.
HR 5553 is a binary star system located thirty-eight light-years away from the Sun, in the northern constellation Boötes. It has the variable star designation DE Boötis, and is classified as an RS Canum Venaticorum variable that ranges in apparent visual magnitude from 5.97 down to 6.04, which is bright enough to be dimly visible to the naked eye. The system is drifting closer to the Sun with a radial velocity of −30 km/s, and is expected to come as close as 26.9 light-years in 210,000 years.
II Pegasi is a binary star system in the constellation of Pegasus with an apparent magnitude of 7.4 and a distance of 130 light-years. It is a very active RS Canum Venaticorum variable, a close binary system with active starspots.
EQ Virginis is a single variable star in the equatorial constellation of Virgo. It has a baseline visual apparent magnitude of 9.36, but is a flare star that undergoes sporadic bursts of brightening. The star is located at a distance of 67 light-years from the Sun based on parallax measurements, but is drifting closer with a radial velocity of −23 km/s. It is a member of the IC 2391 moving group of stars, which is between 30 and 50 million years old.
Omicron Draconis is a giant star in the constellation Draco located 322.93 light years from the Earth. Its path in the night sky is circumpolar for latitudes greater than 31o north, meaning the star never rises or sets when viewed in the night sky.
UX Arietis is a triple star system located in the northern zodiacal constellation of Aries. Based upon parallax measurements from the Gaia satellite, it is roughly 165 light years away. The primary, component Aa, is a variable star of the RS CVn type. The variability of the star is believed due to a combination of cool star spots and warm flares, set against the baseline quiescent temperature of the stellar atmosphere. The variability appears to be cyclical with a period of 8−9 years. The star varies in brightness from magnitude 6.35 to 6.71, meaning it may be intermittently visible to the unaided eye under ideal dark-sky conditions.
3 Camelopardalis is a spectroscopic and visual binary in the constellation Camelopardalis. It is approximately 496 light years from Earth.
RT Andromedae is a variable star in the constellation of Andromeda. The system is estimated to be 322 light-years away.
Chi1 Hydrae is a binary star in the equatorial constellation of Hydra. It originally received the Flamsteed designation of 9 Crateris before being placed in the Hydra constellation. Based upon an annual parallax shift of 22.8 mas as seen from Earth, it is located about 143 light years from the Sun. It is visible to the naked eye with a combined apparent visual magnitude of 4.94.
Sigma Coronae Borealis is a star system in the constellation of Corona Borealis. It is a quintuple star system containing three sunlike main-sequence stars and two other low-mass stars. The combined visual magnitude is 5.3 and the system lies 74 light years from Earth. σ CrB A is the variable star TZ Coronae Borealis.
XX Trianguli, abbreviated XX Tri, is a variable star in the northern constellation of Triangulum, about 1.5° to the WNW of Beta Trianguli along the constellation border with Andromeda. It is classified as a RS Canum Venaticorum variable and ranges in brightness from magnitude 8.1 down to 8.7, which is too faint to be visible to the naked eye. The system is located at a distance of approximately 642 light years from the Sun based on parallax, but is drifting closer with a radial velocity of −26 km/s.
V471 Tauri is an eclipsing variable star in the constellation of Taurus. The star has a visual magnitude of 9 which makes it impossible to see with the naked eye. It is around 155 light-years away from the Solar System.