Delta Draconis

δ Draconis
Location of δ Draconis (circled)
Observation data
Epoch J2000      Equinox J2000
Constellation Draco
Right ascension 19h 12m 33.30137s[1]
Declination +67° 39′ 41.5392″[1]
Apparent magnitude (V) 3.07[2]
Characteristics
Spectral type G9 III[3]
U−B color index +0.78[2]
B−V color index +1.00[2]
Astrometry
Radial velocity (Rv)24.71±0.16[4] km/s
Proper motion (μ) RA: +94.599 mas/yr[1]
Dec.: +92.374 mas/yr[1]
Parallax (π)33.3499 ± 0.1567 mas[1]
Distance97.8 ± 0.5 ly
(30.0 ± 0.1 pc)
Absolute magnitude (MV)+0.62[5]
Details[4]
Mass1.70±0.18 M
Radius10.52±0.24 R
Luminosity59 L
Surface gravity (log g)2.59±0.05 cgs
Temperature4,873±25 K
Metallicity [Fe/H]−0.13±0.05 dex
Rotational velocity (v sin i)8[6] km/s
Age1.66±0.35 Gyr
Other designations
Aldib, Altais,[7] Nodus Secundus,[8] 57 Draconis, HR 7310, BD+67 1129, HD 180711, SAO 18222, FK5 723, HIP 94376.[9]
Database references
SIMBADdata

Delta Draconis (δ Draconis, abbreviated Delta Dra, δ Dra), formally named Altais /ælˈt.ɪs/,[10] is a yellow star in the constellation of Draco. It has an apparent visual magnitude of 3.0,[2] making it easily visible to the naked eye. Based on parallax measurements obtained by the Gaia mission, it is approximately 97.8 light-years (30.0 parsecs) from the Sun.[1]

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  4. ^ a b Cite error: The named reference jofre2015 was invoked but never defined (see the help page).
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  9. ^ Cite error: The named reference simbad was invoked but never defined (see the help page).
  10. ^ "Naming Stars". IAU.org. Retrieved 4 March 2018.