Observation data Epoch J2000.0 Equinox J2000.0 | |
---|---|
Constellation | Centaurus |
Right ascension | 13h 12m 03.18430s [1] |
Declination | −37° 48′ 10.8799″ [1] |
Apparent magnitude (V) | 4.852 ± 0.011 [2] |
Characteristics | |
Spectral type | G4 IV [3] |
B−V color index | 0.659 ± 0.020 [2] |
Astrometry | |
Radial velocity (Rv) | −13.03±0.13 [1] km/s |
Proper motion (μ) | RA: −382.409 mas/yr [1] Dec.: −46.147 mas/yr [1] |
Parallax (π) | 48.8691 ± 0.1058 mas [1] |
Distance | 66.7 ± 0.1 ly (20.46 ± 0.04 pc) |
Absolute magnitude (MV) | 3.29 [4] |
Details | |
Mass | 1.25±0.03 [5] M☉ |
Radius | 2.01±0.06 [5] R☉ |
Luminosity | 4.057±0.014 [6] L☉ |
Surface gravity (log g) | 3.97±0.02 [6] cgs |
Temperature | 5,729±17 [6] K |
Metallicity [Fe/H] | 0.19±0.01 [6] dex |
Rotation | 34.1±3.5 d [7] |
Rotational velocity (v sin i) | 2.4±0.5 [8] km/s |
Age | 5.20±0.24 [5] Gyr |
Other designations | |
Database references | |
SIMBAD | data |
HD 114613 (Gliese 501.2) is a fifth magnitude yellow subgiant that lies 66.7 light-years (20.5 parsecs ) away in the constellation of Centaurus. The star may be host to a long-period giant planet.
HD 114613 lies about two degrees south-east of Iota Centauri, towards the middle of Centaurus. Though it is fairly easily observable with the naked eye, the star does not have a Bayer or Flamsteed designation as the constellation of Centaurus contains many brighter stars.
The B-V colour and spectroscopic temperature of HD 114613 correspond with its spectral type of G4. This means that the star is only slightly cooler than the Sun, and has the yellow hue typical of G-type stars. On the Hertzsprung-Russell diagram (left) the star lies significantly above the main sequence, and is close to the subgiant branch; this means that HD 114613 has depleted the hydrogen in its core through nuclear fusion, and is increasing in radius while decreasing in temperature as it moves towards the giant branch.
As HD 114613 is ending hydrogen fusion, the star must be fairly old. When combined with a spectroscopically-derived mass of 1.25 ± 0.03 M☉ and a surface gravity of log 3.95 ± 0.03 g the implied age of the star is 5.20 ± 0.24 billion years, [5] making it slightly older than the Sun. Though stellar metallicities typically decrease with increasing stellar age, within the age range of the thin disk a wide range of metallicities are common; HD 114613's high iron abundance of 0.19 ± 0.01 dex (155 ± 4% of the solar abundance) is therefore not unusual. The rate of giant planet occurrence for Fe/H = 0.2 dex stars is about 15%, [9] which makes it fairly unsurprising that the star could host a giant planet.
HD 114613 has a magnetic cycle with a period of 897 ± 61 days, about four-and-a-half times shorter than the Solar magnetic cycle and one of the shortest magnetic cycles known. [7]
Being bright and solar-type, HD 114613 is an attractive target for radial velocity (RV)-based planet searches.
HD 114613 was one of the 37 targets of the first RV-based planet search in the southern hemisphere, the ESO-CES survey that spanned between 1992 and 1998. [10] This survey did not detect any companion with several Jovian masses out to a few AU. An extension of this survey to the HARPS spectrograph provides further constraint, suggesting that there are no Jupiter-mass companions out to about 5 AU. [11]
HD 114613 is included in the samples of the ESO-CORALIE [9] and AAT-UCLES [12] planet searches that both began in 1998. Seemingly finding the star to be RV-stable and suitable for higher precision, HD 114613 was included in a subset of the CORALIE sample that became the sample of the ESO-HARPS high precision planet search that began in 2004, [6] while the star was elevated in importance in the AAT sample in 2005. [13] [14] Though apparently not included in its main sample, HD 114613 is included in the sample of the Keck-HIRES Eta-Earth low-mass planet search that also began in 2004. [15]
In Wittenmyer et al. 2012, [16] HD 114613 is indicated to be a low-mass planet host. Though this references a Tuomi et al. 2012 (Tuomi, M., et al. 2012, MNRAS, submitted), no such paper was published that year. More recently, in a Tuomi et al. 2013, [17] Tau Ceti is noted to have a similar activity index distribution to HD 114613. Again, a Tuomi et al. 2012 is referenced, though somewhat more completely (Tuomi, M., Jones, H. R. A., Jenkins, J. S., et al. 2012, MNRAS, submitted). No paper announcing HD 114613 as a low-mass planet host has been published as of 2014.
However, that does not mean the star is not a planet host. Wittenmyer et al. (2014) found HD 114613 to show a moderate-amplitude variation in its radial velocity with a period of 10.5 years, indicative of a long-period companion. [18] The radial velocity semi-amplitude of 5.5 m/s translates to a planet with a minimum mass about half a Jupiter mass. The planet has an intermediate orbital eccentricity of 0.25, which means that it can be somewhat loosely considered a Jupiter analogue.
A study in 2023 did not detect this radial velocity signal, but instead detected a signal with a longer period of about 18 years, which shows indications of originating from a long-period magnetic activity cycle. This suggests that the previously detected signal is not planetary, but is related to stellar activity. [19] : 28 [19] : 44
Companion (in order from star) | Mass | Semimajor axis (AU) | Orbital period (days) | Eccentricity | Inclination | Radius |
---|---|---|---|---|---|---|
b(unconfirmed) | ≥0.48 ± 0.04 MJ | 5.16 ± 0.13 | 3827 ± 105 | 0.25 ± 0.08 | — | — |
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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 75289 is a faint double star in the southern constellation of Vela. The primary component has a yellow hue and an apparent visual magnitude of 6.35. Under exceptionally good circumstances it might be visible to the unaided eye; however, usually binoculars are needed. The pair are located at a distance of 95 light years from the Sun based on parallax, and are drifting further away with a radial velocity of +10 km/s.
HD 20367 is a star in the constellation of Aries, close to the border with the Perseus constellation. It is a yellow-white hued star that is a challenge to view with the naked eye, having an apparent visual magnitude of 6.40. Based upon parallax measurements, it is located 85 light years from the Sun. It is drifting further away with a radial velocity of +6.5 km/s. Based upon its movement through space, it is a candidate member of the Ursa Major Moving Group of co-moving stars that probably share a common origin.
HD 65216 is a triple star system with two exoplanetary companions in the southern constellation of Carina. With an apparent visual magnitude of 7.97 it cannot be readily seen without technical aid, but with binoculars or telescope it should be visible. The system is located at a distance of 114.7 light-years from the Sun based on parallax measurements, and is drifting further away with a radial velocity of 42.6 km/s.
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 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 80606 and HD 80607 are two stars comprising a binary star system. They are approximately 217 light-years away in the constellation of Ursa Major. Both stars orbit each other at an average distance of 1,200 astronomical units. The binary system is listed as Struve 1341 in the Struve Catalogue of Double Stars; however, this designation is not in wide use and the system is usually referred to by the HD designations of its constituent stars. An extrasolar planet has been confirmed to orbit HD 80606 in a highly elliptical orbit.
Nu Phoenicis is a F-type main-sequence star in the southern constellation of Phoenix. It is visible to the naked eye with an apparent visual magnitude of 4.95. This is a solar analogue, meaning its observed properties appear similar to the Sun, although it is somewhat more massive. At an estimated distance of around 49.5 light years, this star is located relatively near the Sun.
HD 172051 is a single, yellow-hued star in the southern constellation of Sagittarius. The star is barely bright enough to be seen with the naked eye, having an apparent visual magnitude of 5.85. Based upon an annual parallax shift of 76.64 mas, it is located some 43 light years from the Sun. It is moving away from the Sun with a radial velocity of +37 km/s.
HD 154857 is a star with two exoplanetary companions in the southern constellation of Ara. It is too dim to be visible with the naked eye having an apparent visual magnitude of 7.25. The star is located at a distance of 207 light years from the Sun based on parallax measurements, and is drifting further away with a radial velocity of +28 km/s.
Gliese 86 is a K-type main-sequence star approximately 35 light-years away in the constellation of Eridanus. It has been confirmed that a white dwarf orbits the primary star. In 1998 the European Southern Observatory announced that an extrasolar planet was orbiting the star.
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HD 85390 is a star with an exoplanet companion in the southern constellation of Vela. It was given the proper name Natasha by Zambia during the 100th anniversary of the IAU. Natasha means "thank you" in many languages of Zambia. This star is too faint to be seen with the naked eye, having an apparent visual magnitude of 8.54. It is located at a distance of 109 light years from the Sun based on parallax, and is drifting further away with a radial velocity of 33 km/s.
Gliese 179 is a small red dwarf star with an exoplanetary companion in the equatorial constellation of Orion. It is much too faint to be visible to the naked eye with an apparent visual magnitude of 11.94. The system is located at a distance of 40.5 light-years from the Sun based on parallax measurements, but is drifting closer with a radial velocity of –9 km/s. It is a high proper motion star, traversing the celestial sphere at an angular rate of 0.370″·yr−1.
HD 175167 is a star with an exoplanet companion in the southern constellation of Pavo. It is too faint to be visible with the naked eye at an apparent visual magnitude of 8.01. The system is located at a distance of 232 light years from the Sun based on parallax measurements, and it is drifting further away with a radial velocity of 5 km/s. It shows a high proper motion, traversing the celestial sphere at an angular rate of 0.190 arcsec yr−1.
HD 53705/53706/53680 is a star system that lies approximately 54 light-years away in the constellation of Puppis. The system consists of four stars in two binaries, making it one of the nearest quadruple star systems.
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