HD 172051

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HD 172051
Observation data
Epoch J2000      Equinox J2000
Constellation Sagittarius
Right ascension 18h 38m 53.40s [1]
Declination −21° 03′ 06.7″ [1]
Apparent magnitude (V) 5.866
Characteristics
Spectral type G5 V
U−B color index 0.15
B−V color index 0.65
Variable type None
Astrometry
Radial velocity (Rv)+35.6 km/s
Proper motion (μ) RA: -74.85 ± 0.77 [1] mas/yr
Dec.: -152.00 ± 0.47 [1] mas/yr
Parallax (π)76.43 ± 0.47 mas[1]
Distance42.7 ± 0.3 ly
(13.08 ± 0.08 pc)
Absolute magnitude (MV)5.29
Details
Mass1.0 M
Radius0.86 R
Luminosity0.65 L
Temperature5,580 K
Age(4.1–4.8) × 109[2] years
Other designations
86 G. Sagittarii, GJ 722, HR 6998, BD -21°5081, GCTP 4289.01, SAO 187086, HIP 91438.

HD 172051 (86 G. Sagittarii) is a main sequence dwarf star in the constellation Sagittarius.

It is located about 42 light years from the Sun and is considered a solar analog. It is similar in mass to the Sun, although it is cooler and has a lower luminosity. Due to this similarity, HD 172051 has been selected as an early target star for both the Terrestrial Planet Finder and Darwin missions, which seek to find an Earth-like extrasolar planet.[3]

References

  1. ^ a b c d e van Leeuwen, F. (2007). "HIP 91438". Hipparcos, the New Reduction. Retrieved 2009-12-12.
  2. ^ Mamajek, Eric E.; Hillenbrand, Lynne A. (2008). "Improved Age Estimation for Solar-Type Dwarfs Using Activity-Rotation Diagnostics". The Astrophysical Journal. 687 (2): 1264–1293. Bibcode:2008ApJ...687.1264M. doi:10.1086/591785. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)
  3. ^ "Planet hunters target nearby star". BBC News. 2003-11-07. Retrieved 2006-08-04.

External links