HD 98618

Coordinates: Sky map 11h 21m 29s, +58° 53′ 18″
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HD 98618
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Ursa Major
Right ascension 11h 21m 29.0695s[1]
Declination +58° 29′ 03.7043″[1]
Apparent magnitude (V) 7.66
Characteristics
Spectral type G5V
B−V color index 0.642
Variable type none
Astrometry
Radial velocity (Rv)16 km/s
Proper motion (μ) RA: 41.329±0.057[1] mas/yr
Dec.: 28.415±0.076[1] mas/yr
Parallax (π)24.2400 ± 0.0486 mas[1]
Distance134.6 ± 0.3 ly
(41.25 ± 0.08 pc)
Absolute magnitude (MV)4.74 ± 0.07
Details
Mass1.02±0.03 M
Radius1.00 R
Luminosity1.06 ± 0.05 L
Temperature5843 ± 30 K
Metallicity1.05 sol
Rotation24 days
Age4210 ± 900 million years
Other designations
BD+59°1369, HIP 55459[2]
Database references
SIMBADdata


HD 98618 is a star 126 light years from Earth that is almost identical in most respects to the Sun; it has therefore been proposed as a candidate solar twin.[3] However, like the solar twin 18 Scorpii, HD 98618 has a lithium abundance significantly higher than that of the Sun ([Li/H] = +0.45 ± 0.08).[4] Meléndez & Ramírez (2007) have suggested that HD 98618 be considered a "quasi solar twin", since they have now identified a solar twin, HIP 56948, with lithium content identical within the observational error to the Sun's.

References

  1. ^ a b c d e 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. ^ "HD 98618". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-10-13.
  3. ^ Meléndez, J., & Dodds-Eden, K., & Robles, J. A. (2006). "HD 98618: A Star Closely Resembling Our Sun". The Astrophysical Journal. 641 (2): L133–L136. arXiv:astro-ph/0603219. Bibcode:2006ApJ...641L.133M. doi:10.1086/503898.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  4. ^ Meléndez, J., & Ramírez, I. (2007). "HIP 56948: A Solar Twin with a Low Lithium Abundance". The Astrophysical Journal. 669 (2): L89–L92. arXiv:0709.4290. Bibcode:2007ApJ...669L..89M. doi:10.1086/523942.{{cite journal}}: CS1 maint: multiple names: authors list (link)

External links