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Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Serpens |
Right ascension | 15h 32m 43.65s [1] |
Declination | +10° 58′ 05.9″ [1] |
Apparent magnitude (V) | 7.215 |
Characteristics | |
Spectral type | G5& IV-V [2] |
B−V color index | 0.656 [3] |
Astrometry | |
Distance | 30.24 [3] pc |
Absolute magnitude (MV) | 4.82 [3] |
Details [3] | |
Surface gravity (log g) | 4.42±0.01 cgs |
Temperature | 5,757±10 K |
Metallicity | 0.00±0.01 |
Age | 7.1+4.2 −4.5 Gyr |
Other designations | |
Database references | |
SIMBAD | data |
HD 138573 is a G-type main-sequence star in the constellation Serpens, class G5IV-V, roughly 100.8 light-years from Earth (30.912 parsecs). [1] [2] Though a G-type star like the Sun, a 2005 study found that it is not a solar twin as HD 138573 has a much lower mass, lower metallicity, and is much older age than the Sun at 5.6 billion years old. HD 138573 is otherwise close to the Sun's characteristics and could be classed as a Solar analog. [4]
Mahdi et al. (2016) named the star the best solar twin candidate out of their dataset of around 2,800 candidates. [3]
Chart compares the Sun to HD 138573.
Identifier | J2000 Coordinates | Distance (ly) | Stellar Class | Temperature (K) | Metallicity (dex) | Age (Gyr) | Notes | |
---|---|---|---|---|---|---|---|---|
Right ascension | Declination | |||||||
Sun | — | — | 0.00 | G2V | 5,778 | +0.00 | 4.6 | [5] |
HD 138573 [6] | 15h 32m 43.7s | +10° 58′ 06″ − | 101 − | G5IV-V − | 5,689 − | −0.10 − | 5.6 − | [2] − |
Solar-type star, solar analogs, and solar twins are stars that are particularly similar to the Sun. The stellar classification is a hierarchy with solar twin being most like the Sun followed by solar analog and then solar-type. Observations of these stars are important for understanding better the properties of the Sun in relation to other stars and the habitability of planets.
Psi Serpentis is a triple star system within the Serpens Caput part of the equatorial constellation Serpens. Based upon an annual parallax shift of 68.22 mas as seen from Earth, it is located approximately 47.8 light years from the Sun. This system came closest approach to the Sun about 585,000 years ago when it made perihelion passage at an estimated distance of 23.27 ly (7.134 pc). Psi Serpentis is faintly visible to the naked eye with an apparent visual magnitude of 5.84.
HD 98618 is a yellow-hued star in the northern circumpolar constellation of Ursa Major. It is invisible to the naked eye, having an apparent visual magnitude of just 7.65. Based on measurements, this star is located at a distance of 135 light years from the Sun based on parallax, and is drifting further away with a radial velocity of +7.1 km/s. It is a likely member of the thin disk population and is orbiting the Milky Way at about the same distance from the Galactic Center as 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 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 138 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 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 6718 is a solar twin star in the equatorial constellation of Cetus. It has a yellow hue but is too faint to be viewed with the naked eye, having an apparent visual magnitude of 8.45. The distance to this object, as determined from parallax measurements, is 168 light years. It is drifting away from the Sun with a radial velocity of +35 km/s.
HD 9446 is a star located about 164 light-years away in the constellation of Triangulum, near the southwestern constellation border with Pisces. This object can be viewed with binoculars or a telescope, but it is too faint to be seen with the naked eye at its apparent visual magnitude of 8.35. It is drifting further away from the Sun with a radial velocity of +21 km/s.
HD 129357 is a G-type star in the constellation Boötes that is located about 154 light years from the Sun. The measured properties of this star are very similar to those of the Sun, making it a candidate solar twin. However, it has a lower abundance of lithium than the Sun and appears over 3 billion years older, so it may instead be a solar analog. It was suggested by astronomer Olin Eggen that this star is a member of the Wolf 630 moving group of stars that share a common motion through space. The space velocity components of HD 129357 are (U, V, W) = (+21.3, −36.3, −32.0).
HD 202628 is a single star in the southern constellation of Microscopium. It has an apparent visual magnitude of +6.7, which makes it too faint to be readily visible to the naked eye. The star is located at a distance of 77.7 light years from the Sun based on parallax, and it is drifting further away with a radial velocity of +12.1 km/s. The absolute magnitude of this star is 4.86.
HIP 100963 is a G-type star in the faint northern constellation of Vulpecula resembling the Sun. It has an apparent visual magnitude of approximately 7.1, making it generally too faint to be seen with the naked eye in most circumstances. The distance to this star, as determined using parallax measurements from the Gaia spacecraft, is around 92 light-years.
HD 197027 is a star in the constellation Capricornus. It has an apparent magnitude of 9.15, making it readily visible through a telescope but not to the naked eye. The object is located at a distance of 255 light years but is approaching the Solar System with a heliocentric radial velocity of −44 km/s.
HD 45184 is a star in the southern constellation of Canis Major. It is a yellow-hued star near the lower limit of visibility to the naked eye with an apparent visual magnitude of 6.37. The star is located at a distance of 71.65 light years from the Sun based on parallax. It is drifting closer with a radial velocity of −3.8 km/s.
HIP 11915 is a G-type main-sequence star located about 190 light-years from Earth in the constellation Cetus. It is best known for its characteristics, which are very similar to those of the Sun, including the mass, radius, temperature, metallicity and age, which means that it is almost a solar twin, being just 500 million years younger than the Sun and with a lower metallicity. It is also known for its planetary companion, HIP 11915 b, which has a mass and orbital distance very similar to that of Jupiter, but probably with a slightly higher orbital eccentricity.
HD 150248 is a Sun-like star 87 light-years from the Sun. HD 150248 is a G-type star and a near solar twin. HD 150248's photometric color is also very close to that of the Sun; however, it has a lower abundance of metals, and has an apparent visual magnitude of 7.02. At 6.2 billion years old, this star is 1.6 billion years older than the Sun and has passed the stable burning stage. HD 150248 is found on the border between the constellations Scorpius and Ara.
HD 117939 is a Sun-like star in the southern constellation of Centaurus. With an apparent visual magnitude of 7.29 it is too faint to be viewed with the naked eye, but is within the range of binoculars or a small telescope. It is located at a distance of 98.5 light years from the Sun based on parallax measurements, and is drifting further away with a radial velocity of +82 km/s. This is an intermediate disk star with a high proper motion, traversing the celestial sphere at an angular rate of 0.68 arcsec yr−1.
HD 71334 is a Sun-like star 126.7 light years from the Sun. HD 150248 is a G-type star and an older solar analog. It is older than the sun at 8.1 billion years, compared to the sun at 4.6 billion years old. At 8.1 billion years old, HD 71334 has passed its stable burning stage. HD 71334 has a lower metallicity that the Sun. HD 71334 is found in the constellations of Puppis. Puppis is one of the 88 modern constellations recognized by the International Astronomical Union. HD 71334 has a brightness of 7.8.
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 133131 is a binary star in the constellation of Libra. It is roughly 168 light-years away from the Sun. It consists of two G-type main-sequence stars; neither are bright enough to be seen with the naked eye.
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.