HD 220074

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HD 220074
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Cassiopeia
Right ascension 23h 20m 14.37962s[1]
Declination +61° 58′ 12.4578″[1]
Apparent magnitude (V) +6.39
Characteristics
Spectral type M2III[2][1]
Astrometry
Radial velocity (Rv) – 36.89 ± 0.21[2] km/s
Proper motion (μ) RA: ? mas/yr
Dec.: ? mas/yr
Parallax (π) 3.08 ± 0.43[2] ± ? mas
Distance ? ly
(290.2 ± 45.5[1] pc)
Absolute magnitude (MV) – 1.52[2]
Details
Mass 1.2 ± 0.3[1] M
Radius 49.7 ± 9.5[1] R
Luminosity L
Surface gravity (log g) 1.3 ± 0.5[2] cgs
Temperature 3935 ± 110[2] K
Metallicity –0.25 ± 0.25[1]
Rotation 3.0[2]
Age 4.5 ± 2.8 × 109[1] years
Other designations
HD 220074, HIP 115218, HR 8881
Database references
SIMBAD data
Exoplanet Archive data
Extrasolar Planets
Encyclopaedia
data

HD 220074 is a M2III red giant star located in Cassiopeia.

It had been considered K1V but is now known as M2III due to radius and surface gravity.[2]

Planetary system[edit]

From September 2008 to June 2012, the team B.-C. Lee, I. Han, and M.-G. Park observed HD 220074 with "the high-resolution spectroscopy of the fiber-fed Bohyunsan Observatory Echelle Spectrograph (BOES) at Bohyunsan Optical Astronomy Observatory (BOAO)".

In 2012, a long-period, wide-orbiting eccentric planet was deduced by radial velocity. This was published in November, gaining the designation HD 220074 b.[1] Along with HD 208527 b this is one of the first two planets proposed around a red giant.

The HD 220074 system[1]
Companion
(in order from star)
Mass Semimajor axis
(AU)
Orbital period
(days)
Eccentricity Inclination Radius
b >11.1 ± 1.8 MJ 1.6 ± 0.1 672.1 ± 3.7 0.14 ± 0.05

References[edit]

  1. ^ a b c d e f g h i j "hd_220074_b". 
  2. ^ a b c d e f g h B.-C. Lee, I. Han, M.-G. Park (2012). "Planetary companions orbiting M giants HD208527 and HD 220074". Astronomy & Astrophysics. arXiv:1211.2051. doi:10.1051/0004-6361/201220301. 

External links[edit]