HIP 100963

HIP 100963 is a G-type star in the faint northern constellation of Vulpecula[4] resembling the Sun. It has an apparent visual magnitude of approximately 7.1,[4] 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 (28 parsecs).[1]

HIP 100963

Observation data Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation	Vulpecula
Right ascension	20^h 28^m 11.8156^s[1]
Declination	+22° 07′ 44.3670″[1]
Apparent magnitude (V)	+7.088[2]
Characteristics
Spectral type	G5[3]
B−V color index	+0.65[4]
V−R color index	+0.39[4]
R−I color index	+0.3[4]
Astrometry
Radial velocity (Rv)	−1.6[5] km/s
Proper motion (μ)	RA: −22.734±0.065[1] mas/yr Dec.: −243.722±0.060[1] mas/yr
Parallax (π)	35.5142 ± 0.0571[1] mas
Distance	91.8 ± 0.1 ly (28.16 ± 0.05 pc)
Details
Mass	0.998 ± 0.006[6] M☉
Luminosity	0.968 ± 0.043[6] L☉
Temperature	5,779 ± 50[6] K
Metallicity [Fe/H]	−0.002[6] dex
Rotational velocity (v sin i)	2.39[7] km/s
Age	2.01–3.80[6] Gyr
Other designations
BD+21 4221, HD 195034, LTT 15980, NLTT 49310, PPM 111203, SAO 88711.[4]
Database references
SIMBAD	data

This star has a stellar classification of G5,[4] making it a G-type star with an undetermined luminosity class. It has similar mass, temperature and chemical abundance to the Sun and was called a solar twin in a 2009 study, although its lithium abundance is three to four times that of the Sun and it is much younger. This lithium excess suggests that the star has a younger age of between 2.01 and 3.80 billion years, compared to the previous estimate of 5.13+0.00
−2.99 Gyr from a 2007 study.[6]

Sun comparison

Chart compares the sun to HIP 100963/HP 195034.

− − − − −

Identifier −	J2000 Coordinates −		Distance (ly) −	Stellar Class −	Temperature (K) −	Metallicity (dex) −	Age (Gyr) −	Notes −
	Right ascension −	Declination −
HD 195034 [8] −	20^h 28^m 11.8^s −	+22° 07′ 44″ −	92 −	G5 −	5,779 −	−0.002 −	2.9 −	−
Sun −	— −	— −	0.00 −	G2V −	5,778 −	+0.00 −	4.6 −	−

References

1. Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
2. Høg, E.; et al. (2000). "The Tycho-2 catalogue of the 2.5 million brightest stars". Astronomy and Astrophysics. 355: L27–L30. Bibcode:2000A&A...355L..27H.
3. White, Russel J.; Gabor, Jared M.; Hillenbrand, Lynne A. (June 2007), "High-Dispersion Optical Spectra of Nearby Stars Younger Than the Sun", The Astronomical Journal, 133 (6): 2524–2536, arXiv:0706.0542, Bibcode:2007AJ....133.2524W, doi:10.1086/514336
4. "HD 195034". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved May 23, 2016.
5. Nordström, B.; et al. (May 2004). "The Geneva-Copenhagen survey of the Solar neighbourhood. Ages, metallicities, and kinematic properties of ˜14 000 F and G dwarfs". Astronomy and Astrophysics. 418 (3): 989–1019. arXiv:astro-ph/0405198. Bibcode:2004A&A...418..989N. doi:10.1051/0004-6361:20035959.. See the Vizier entry for this star.
6. Do Nascimento, J. D., Jr.; et al. (July 2009). "Age and mass of solar twins constrained by lithium abundance". Astronomy and Astrophysics. 501 (2): 687–694. arXiv:0904.3580. Bibcode:2009A&A...501..687D. doi:10.1051/0004-6361/200911935.
7. Takeda, Y.; et al. (June 2010), "Behavior of Li abundances in solar-analog stars. II. Evidence of the connection with rotation and stellar activity", Astronomy and Astrophysics, 515: A93, arXiv:1003.1564, Bibcode:2010A&A...515A..93T, doi:10.1051/0004-6361/200913897
8. HD 195034 at SIMBAD - Ids - Bibliography - Image.