Observation data Epoch J2000.0 Equinox J2000.0 | |
---|---|
Constellation | Crater |
Right ascension | 11h 20m 51.76855s [1] |
Declination | −23° 13′ 02.4295″ [1] |
Apparent magnitude (V) | +8.00 [2] |
Characteristics | |
Spectral type | G4V |
B−V color index | +0.658 ± 0.003 [3] |
Astrometry | |
Radial velocity (Rv) | 4.25±0.12 [1] km/s |
Proper motion (μ) | RA: −199.735±0.022 mas/yr [1] Dec.: −177.620±0.017 mas/yr [1] |
Parallax (π) | 23.7206 ± 0.0216 mas [1] |
Distance | 137.5 ± 0.1 ly (42.16 ± 0.04 pc) |
Absolute magnitude (MV) | +4.91 [2] |
Details | |
Mass | 0.97±0.02 [4] M☉ |
Radius | ~1 [2] R☉ |
Luminosity (bolometric) | 0.968±0.019 [4] L☉ |
Luminosity (visual, LV) | 0.83 [note 1] L☉ |
Surface gravity (log g) | 4.38 ± 0.08 [2] cgs |
Temperature | 5759 ± 35 [2] K |
Metallicity [Fe/H] | –0.02 ± 0.03 [2] dex |
Rotation | 27 ± 4.0 days [2] |
Rotational velocity (v sin i) | 1.19 [2] km/s |
Age | 4.44+0.68 −0.58 [4] Gyr |
Other designations | |
Database references | |
SIMBAD | data |
Exoplanet Archive | data |
Extrasolar Planets Encyclopaedia | data |
HD 98649 is a G-type yellow dwarf star, classified as a G4V, that has approximately the same mass and diameter as the Sun, but has only 86% of its luminosity. It is considered a solar analog. [4] HD 98649 is about 138 light-years from earth. HD 98649 is found in the Crater constellation. [2]
From 1998 to 2012, the star was under observance from the CORALIE echelle spectrograph at La Silla Observatory.
In 2012, a long-period, wide-orbiting planet was deduced by radial velocity. This was published in November.
The discoverers noted, "HD 98649b is in the top five of the most eccentric planetary orbit and the most eccentric planet known with a period larger than 600 days." The reason for this eccentricity is unknown. They also submit it as a candidate for direct imaging, once it gets out to 10.4 AU at apoastron and 250 milliarcseconds of separation relative to Earth. [2]
Using astrometry from Gaia , astronomers were able to deduce the true mass of HD 98649 b as 9.7 MJ, somewhat higher than its minimum mass from radial velocity. [4] [5]
Companion (in order from star) | Mass | Semimajor axis (AU) | Orbital period (years) | Eccentricity | Inclination | Radius |
---|---|---|---|---|---|---|
b | 9.7+2.3 −1.9 MJ | 5.97+0.24 −0.21 | 14.74+0.88 −0.75 | 0.852+0.033 −0.022 | 43.7+13 −8.1 ° | — |
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.
Gliese 229 is a binary system composed of a red dwarf and the first brown dwarf seen by astronomers, 18.8 light years away in the constellation Lepus. The primary component has 58% of the mass of the Sun, 69% of the Sun's radius, and a very low projected rotation velocity of 1 km/s at the stellar equator.
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 11506 is a star in the equatorial constellation of Cetus. It has a yellow hue and can be viewed with a small telescope but is too faint to be visible to the naked eye, having an apparent visual magnitude of 7.51. The distance to this object is 167 light years based on parallax, but it is drifting closer to the Sun with a radial velocity of −7.5 km/s. It has an absolute magnitude of 3.94.
HD 4113 is a dual star system in the southern constellation of Sculptor. It is too faint to be viewed with the naked eye, having an apparent visual magnitude of 7.88. The distance to this star, as estimated by parallax measurements, is 137 light years. It is receding away from the Sun with a radial velocity of +5 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 142415 is a single star in the southern constellation of Norma, positioned next to the southern constellation border with Triangulum Australe and less than a degree to the west of NGC 6025. With an apparent visual magnitude of 7.33, it is too faint to be visible to the naked eye. The distance to this star is 116 light years from the Sun based on parallax, but it is drifting closer with a radial velocity of −12 km/s. It is a candidate member of the NGC 1901 open cluster of stars.
HD 162020 is a star in the southern constellation of Scorpius with a likely red dwarf companion. It has an apparent visual magnitude of 9.10, which is too faint to be visible to the naked eye. The distance to this system is 101 light years based on stellar parallax. It is drifting closer to the Sun with a radial velocity of −27 km/s, and is predicted to come to within ~18 light-years in 1.1 million years.
HD 40307 is an orange (K-type) main-sequence star located approximately 42 light-years away in the constellation of Pictor, taking its primary name from its Henry Draper Catalogue designation. It is calculated to be slightly less massive than the Sun. The star has six known planets, three discovered in 2008 and three more in 2012. One of them, HD 40307 g, is a potential super-Earth in the habitable zone, with an orbital period of about 200 days. This object might be capable of supporting liquid water on its surface, although much more information must be acquired before its habitability can be assessed.
HD 88836, also known as HR 4019, is a solitary, yellow-hued star located in the southern constellation Antlia. It has an apparent magnitude of 6.32, placing it near the limit for naked eye visibility. Based on an annual parallax shift of 7.019 mas, the object is estimated to be 465 light years away from the Solar System. Its distance from the Sun does not appear to be changing, having a radial velocity of 0 km/s.
HD 73267 is a star in the southern constellation Pyxis, near the western constellation border with Puppis. It has an apparent visual magnitude of 8.889 and can be viewed with a small telescope. The distance to HD 73267 is 164 light years based on parallax, and it is drifting further away with a radial velocity of +51.8 km/s. It has an absolute magnitude of 5.24.
HD 204313 is a star with two and possibly three exoplanetary companions in the southern constellation of Capricornus. With an apparent magnitude of 7.99, it is an eighth magnitude star that is too faint to be readily visible to the naked eye. The star is located at a distance of 157 light years from the Sun based on parallax measurements, but it is drifting closer with a radial velocity of −10 km/s.
HD 219077 is a faint, yellow-hued star in the southern constellation of Tucana. It has an apparent visual magnitude of +6.12, which is near the lower limit on stars visible to the naked eye. Based upon an annual parallax shift of 34.25 mas as seen from Earth, it lies 95 light years from the Sun. HD 219077 is moving closer to the Sun with a radial velocity of −31.01, and has a relatively high proper motion.
HD 166724 is a star in the southern constellation of Corona Australis. It is invisible to the naked eye with an apparent visual magnitude of +9.33. The star is located at a distance of 147 light years from the Sun based on parallax, but is drifting closer with a radial velocity of −18 km/s. It is predicted to come as close as 97.0 light-years in around 1.2 million years from now. The star has an absolute magnitude of 6.20.
HD 106515 is a binary star in the constellation of Virgo.
Mu2 Octantis (μ2 Oct) is a binary star system of two G-type main-sequence stars. It shares the designation μ with μ1 Octantis, from which it is separated by 50 arcminutes.
HD 83380 is an orange-hued star in the southern constellation of Antlia. It shines faintly with a apparent magnitude of 5.62 when viewed in ideal conditions. Parallax measurements place the object at distance of 312 light-years. It has a heliocentric radial velocity of −2.6 km/s, indicating that it is drifting towards the Solar System.
HD 191806 is a star located in the northern constellation Cygnus. With an apparent magnitude of 8.093, it's undetectable with the naked eye, but can be seen with binoculars. HD 191806 is currently placed at a distance of 215 light years based on parallax measurements and is drifting towards the Solar System with a spectroscopic radial velocity of −15.28 km/s.
HD 121056, also known as HIP 67851, is a K-type giant star 209 light-years away in the constellation of Centaurus. Its surface temperature is 4867±49 K. HD 121056’s concentration of heavy elements is similar to the Sun, with a metallicity Fe/H index of 0.020±0.031, although the star is enriched in lighter rock-forming elements like magnesium and aluminum.
HD 222060, also known as HR 8957, is a solitary, orange hued star located in the southern circumpolar constellation Octans. It has an apparent magnitude of 5.98, allowing it to be faintly visible to the naked eye. Based on parallax measurements from GAIA, the object is estimated to be 536 light years distant. It appears to be slowly receding from the Solar System, having a heliocentric radial velocity of 2.3 km/s.