Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Centaurus |
HD 102365 A | |
Right ascension | 11h 46m 31.07253s [1] |
Declination | −40° 30′ 01.2859″ [1] |
Apparent magnitude (V) | 4.88 [2] |
HD 102365 B | |
Right ascension | 11h 46m 32.68988s [3] |
Declination | −40° 29′ 47.6048″ [3] |
Apparent magnitude (V) | 15 [4] |
Characteristics | |
Spectral type | G2V [5] + M4V [6] |
U−B color index | 0.10 [2] |
B−V color index | 0.67 [2] |
Astrometry | |
HD 102365 A | |
Radial velocity (Rv) | 16.94±0.12 [1] km/s |
Proper motion (μ) | RA: −1530.971 mas/yr [1] Dec.: +403.287 mas/yr [1] |
Parallax (π) | 107.3024 ± 0.0873 mas [1] |
Distance | 30.40 ± 0.02 ly (9.319 ± 0.008 pc) |
Absolute magnitude (MV) | 5.07 [7] |
HD 102365 B | |
Radial velocity (Rv) | 17.23±0.27 [3] km/s |
Proper motion (μ) | RA: −1534.679 mas/yr [3] Dec.: +381.396 mas/yr [3] |
Parallax (π) | 107.4237 ± 0.0351 mas [3] |
Distance | 30.362 ± 0.010 ly (9.309 ± 0.003 pc) |
Details | |
A | |
Mass | 0.889 [8] M☉ |
Radius | 0.96 [8] R☉ |
Luminosity | 0.85 [9] L☉ |
Surface gravity (log g) | 4.51 [5] cgs |
Temperature | 5,643 [9] K |
Metallicity [Fe/H] | −0.28 [9] dex |
Rotational velocity (v sin i) | 0.5 [10] km/s |
Age | 4.5–5.7 [11] Gyr |
Other designations | |
Database references | |
SIMBAD | A |
B | |
ARICNS | data |
HD 102345 (66 G. Centauri) is a binary star system that is located in the northeastern part of the Centaurus constellation, at a distance of about 30.4 light-years (9.3 parsecs ) from the Solar System. The larger member of the system is a G-type star that is smaller than the Sun but of similar mass. It has a common proper motion companion that was discovered by W. J. Luyten in 1960. [6] This M-type star appears to be in a wide orbit around the primary at a current separation of about 211 astronomical units (AU), [6] (or 211 times the separation of the Earth from the Sun). By comparison, Neptune orbits at an average distance of 30 AU.
The stellar classification for the primary star in this system is G2V; [5] the same as the Sun. That of the red dwarf companion is M4V. [6] The primary star has an estimated 86% [13] to 89% the mass of the Sun, 96% of the Sun's radius, [8] and 85% of the Sun's luminosity. [9] It is a slow rotator, with a projected rotational velocity of 0.5 km/s. [10] Age estimates range from 4.5 to 5.7 billion years (Gyr) [11] up to 7.1 Gyr [7] or 9.48 Gyr. [8] Compared to the Sun, it only has about 52% [14] of the abundance of elements other than hydrogen and helium; what astronomers term the metallicity of a star.
This star system has a relatively large proper motion. [12] The HR 4523 system is presently located within the Epsilon Indi Moving Group, although it gives itself away as an interloper, since the star is older and has a different composition than the group members. [15] It has space velocity components [U, V, W] = [−67, −40, +4] km/s. [16]
The primary star is believed to be orbited by a Neptune-like planet with a minimum mass 16 times that of the Earth. The orbital period of this planet is 122.1 days. No other planets have been discovered orbiting this star. [17] While a 2013 study was unable to confirm this planet, [18] it was confirmed by a 2023 study, with updated parameters. [19] : 27
An examination of this system in the infrared did not reveal an excess emission that would otherwise suggest the presence of a circumstellar debris disk. [20]
Companion (in order from star) | Mass | Semimajor axis (AU) | Orbital period (days) | Eccentricity | Inclination | Radius |
---|---|---|---|---|---|---|
b | ≥9.34+1.52 −1.5 M🜨 | 0.46±0.04 | 121.3±0.25 | 0.28±0.15 | — | — |
The couch gag for Bart's Not Dead in the television series The Simpsons has an alien family sitting on a couch in this star system. The adult male alien asks why Homer sounds like Walter Matthau.
Chi1 Orionis is a star about 28 light years away. It is in the constellation Orion, where it can be seen in the tip of the hunter's upraised club.
HD 169830 is a star in the southern constellation of Sagittarius. It has a yellow-white hue and is dimly visible to the naked eye with an apparent visual magnitude of +5.90. The star is located at a distance of 120 light years from the Sun based on parallax. It is drifting closer with a radial velocity of −17.3 km/s, and is predicted to come as close as 20.7 ly (6.4 pc) in 2.08 million years. HD 169830 is known to be orbited by two large Jupiter-like exoplanets.
HD 114729 is a Sun-like star with an orbiting exoplanet in the southern constellation of Centaurus. Based on parallax measurements, it is located at a distance of 124 light years from the Sun. It is near the lower limit of visibility to the naked eye, having an apparent visual magnitude of 6.68 The system is drifting further away with a heliocentric radial velocity of 26.3 km/s. The system has a relatively high proper motion, traversing the celestial sphere at an angular rate of 0.373″·yr−1.
HD 114386 is a star with a pair of orbiting exoplanets in the southern constellation of Centaurus. It has an apparent visual magnitude of 8.73, which means it cannot be viewed with the naked eye but can be seen with a telescope or good binoculars. Based on parallax measurements, the system is located at a distance of 91 light years from the Sun. It is receding with a radial velocity of 33.4 km/s. The star shows a high proper motion, traversing the celestial sphere at an angular rate of 0.318 arcsec yr−1.
HR 7703 is a binary star system in the constellation of Sagittarius. The brighter component has an apparent visual magnitude of 5.31, which means it is visible from suburban skies at night. The two stars are separated by an angle of 7.10″, which corresponds to an estimated semimajor axis of 56.30 AU for their orbit.
HD 28185 is a yellow dwarf star similar to the Sun located 128 light-years away from Earth in the constellation Eridanus. The designation HD 28185 refers to its entry in the Henry Draper catalogue. The star is known to possess one long-period extrasolar planet.
HD 142 is a wide binary star system in the southern constellation of Phoenix. The main component has a yellow-white hue and is dimly visible to the naked eye with an apparent visual magnitude of 5.7. The system is located at a distance of 85.5 light years from the Sun based on parallax measurements, and is drifting further away with a radial velocity of +6 km/s.
HD 1237 is a binary star system approximately 57 light-years away in the constellation of Hydrus.
HD 4308 is a single star with an orbiting exoplanet in the southern constellation of Tucana. It has a yellow hue and is a challenge to view with the naked eye even under good seeing conditions, having an apparent visual magnitude of 6.54. This object is located at a distance of 72 light years, as determined from parallax measurements. It is a population II star and is considered to be a member of the thick disk. The star is receding from the Sun with a radial velocity of +95 km/s.
HD 40979 is a triple star system in the northern constellation of Auriga. The combined brightness of this group lies below the typical limit of visibility to the naked eye at an apparent visual magnitude of 6.74. It is located at a distance of approximately 108 light years from the Sun based on parallax. The system is receding with a radial velocity of +32 km/s. It has a relatively high rate of proper motion, traversing the celestial sphere at the rate of 0.182″ per year.
HD 70642 is a star with an exoplanetary companion in the southern constellation of Puppis. It has an apparent visual magnitude of +7.17, which is too dim to be readily visible to the naked eye. The system is located at a distance of 95.5 light-years from the Sun based on parallax measurements, and is drifting further away with a radial velocity of +49.3 km/s. It came to within 55.3 ly of the Solar System some 329,000 years ago.
HD 222582 is a multiple star system in the equatorial constellation of Aquarius. It is invisible to the naked eye with an apparent visual magnitude of 7.7, but can be viewed with binoculars or a small telescope. The system is located at a distance of 137 light years from the Sun based on parallax, and it is drifting further away with a radial velocity of +12 km/s. It is located close enough to the ecliptic that it is subject to lunar occultations.
HD 30177 is a single star with a pair of orbiting exoplanets in the southern constellation Dorado. Based on parallax measurements, it is located at a distance of 181 light years from the Sun. It has an absolute magnitude of 4.72, but at that distance the star is too faint to be viewed by the naked eye with an apparent visual magnitude of 8.41. The star is drifting further away with a radial velocity of 62.7 km/s.
HD 111232 is a star in the southern constellation of Musca. It is too faint to be visible with the naked eye, having an apparent visual magnitude of 7.59. The distance to this star is 94.5 light years based on parallax. It is drifting away from the Sun with a radial velocity of +104 km/s, having come to within 14.1 light-years some 264,700 years ago. The absolute magnitude of this star is 5.25, indicating it would have been visible to the naked eye at that time.
HD 41742 and HD 41700 is a star system that lies approximately 88 light-years away in the constellation of Puppis. The system consists of two bright stars where the primary is orbited by two fainter stars, making it a quadruple with an unequal hierarchy.
Gliese 251, also known as HIP 33226 or HD 265866, is a star located about 18 light years away from the Solar System. Located in the constellation of Gemini, it is the nearest star in this constellation. It is located near the boundary with Auriga, 49 arcminutes away from the bright star Theta Geminorum; due to its apparent magnitude of +9.89 it cannot be observed with the naked eye. The closest star to Gliese 251 is QY Aurigae, which is located 3.5 light years away.
HD 168009 is a star in the northern constellation of Lyra. It has an apparent visual magnitude of 6.3, placing it just above to below the normal limit of stars visible to the naked eye under good viewing conditions of 6-6.5. An annual parallax shift of 42.93 mas provides a distance estimate of 76 light years. It is moving closer to the Sun with a heliocentric radial velocity of −65 km/s. In about 328,000 years from now, the star will make its closest approach at a distance of around 17 ly (5.1 pc).
HD 189567 is a star with a pair of orbiting exoplanets, located in the southern constellation of Pavo. It is also known as Gliese 776, CD-67 2385, and HR 7644. The star has an apparent visual magnitude of 6.07, which is bright enough for it to be dimly visible to the naked eye. It lies at a distance of 58 light years from the Sun based on parallax measurements, but is drifting closer with a radial velocity of −10.5 km/s.
HD 42618 is a well-studied star with an exoplanetary companion in the equatorial constellation of Orion. With an apparent visual magnitude of 6.85 it is too faint to be readily visible to the naked eye. This system is located at a distance of 79.6 light years from the Sun based on parallax measurements. It has a relatively high proper motion, traversing the celestial sphere at an angular rate of 0.321″ per year. HD 42618 is drifting closer with a radial velocity of −53.5 km/s and is predicted to come as near as 42.6 light-years in around 297,000 years.
{{citation}}
: CS1 maint: location missing publisher (link)