42 Draconis

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42 Draconis b
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Draco
Right ascension 18h 25m 59.14s[1]
Declination +65° 33′ 48.5″[1]
Apparent magnitude (V) 4.833
Characteristics
Spectral type K1.5III
B−V color index 1.187
Astrometry
Radial velocity (Rv) 32.17 ± 0.20 km/s
Proper motion (μ) RA: 105.83 ± 0.21[1] mas/yr
Dec.: -27.24 ± 0.28[1] mas/yr
Parallax (π) 10.36 ± 0.20[1] mas
Distance 315 ± 6 ly
(97 ± 2 pc)
Absolute magnitude (MV) –0.108
Details
Mass 0.98 ± 0.05 M
Radius 22.03 ± 1 R
Luminosity 135 L
Surface gravity (log g) 0.929 cgs
Temperature 4200 ± 70 K
Metallicity 35% Sun
Age 9.49 × 109 years
Other designations
BD+65°1271, GC 25212, GCRV 10941, HD 170693, HIP 90344, HR 6945, PPM 20916, SAO 17888
Database references
SIMBAD data
Exoplanet Archive data
Extrasolar Planets
Encyclopaedia
data

42 Draconis (sometimes abbreviated 42 Dra) is a 5th magnitude K-type giant star located approximately 315 light years away in the constellation of Draco. The star has mass similar to our Sun but its radius is 22 times greater. It is a metal-poor star with metallicity as low as 35% that of our Sun and its age is 9.49 billion years. In 2009, this star was found to have a super-Jupiter in orbit around it.

The 42 Draconis planetary system[2]
Companion
(in order from star)
Mass Semimajor axis
(AU)
Orbital period
(days)
Eccentricity Inclination Radius
b ≥3.88 ± 0.85 MJ 1.19 ± 0.01 479.1 ± 6.2 0.38 ± 0.06

Pole star[edit]

42 Draconis is the northern pole star of Venus.

See also[edit]

References[edit]

Coordinates: Sky map 18h 25m 59.1381s, +65° 33′ 48.530″