Eta Draconis

η Draconis
Location of η Draconis (circled)
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Draco
Right ascension 16h 23m 59.48594s[1]
Declination +61° 30′ 51.1699″[1]
Apparent magnitude (V) +2.73[2]
Characteristics
Spectral type G8 III[2]
U−B color index +0.70[3]
B−V color index +0.91[3]
Astrometry
Radial velocity (Rv)–14.3[4] km/s
Proper motion (μ) RA: –17.02[1] mas/yr
Dec.: +56.95[1] mas/yr
Parallax (π)35.42 ± 0.09 mas[1]
Distance92.1 ± 0.2 ly
(28.23 ± 0.07 pc)
Absolute magnitude (MV)+0.58[5]
Details
A
Mass2.55±0.26[6] M☉
Radius10.46[7]–10.53[8] R☉
Luminosity65.6±6.3[8] L☉
Surface gravity (log g)2.82±0.11[6] cgs
Temperature5,018[7] K
Metallicity [Fe/H]–0.088[7] dex
Rotational velocity (v sin i)8[9] km/s
Age650±100[8] Myr
B
Mass0.672[10] M☉
Radius0.577[10] R☉
Luminosity0.206[10] L☉
Temperature5,114[10] K
Other designations
Aldibain, Athebyne, 14 Draconis, BD+61 1591, FK5 822, HD 148387, HIP 80331, HR 6132, NSV 7713, SAO 17074, WDS 16240+6131.[11]
Database references
SIMBADdata

Eta Draconis (η Draconis, abbreviated Eta Dra, η Dra) is a binary star in the northern circumpolar constellation of Draco. Despite having an apparent visual magnitude of only +2.73,[2] it is the second-brightest star in this generally faint constellation. Based upon parallax measurements collected during the Hipparcos mission, this star is located at a distance of about 92.1 light-years (28.2 parsecs) from the Sun.[1]

The two components are designated Eta Draconis A (also named Athebyne /ˈæθɪbaɪn/[12]) and B.

  1. ^ a b c d e f Cite error: The named reference aaa474_2_653 was invoked but never defined (see the help page).
  2. ^ a b c Cite error: The named reference pasj60_4_781 was invoked but never defined (see the help page).
  3. ^ a b Cite error: The named reference aass34_1 was invoked but never defined (see the help page).
  4. ^ Cite error: The named reference gcsrv was invoked but never defined (see the help page).
  5. ^ Cite error: The named reference aaa361_614 was invoked but never defined (see the help page).
  6. ^ a b Cite error: The named reference rosas-portilla was invoked but never defined (see the help page).
  7. ^ a b c Cite error: The named reference gray2019 was invoked but never defined (see the help page).
  8. ^ a b c Cite error: The named reference Baines2018 was invoked but never defined (see the help page).
  9. ^ Cite error: The named reference coapa239_1 was invoked but never defined (see the help page).
  10. ^ a b c d Cite error: The named reference Hardegree-Ullman was invoked but never defined (see the help page).
  11. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  12. ^ "Naming Stars". IAU.org. Retrieved 16 December 2017.