HD 108874

HD 108874

Orbits around the star HD108874
Observation data
Epoch J2000      Equinox J2000
Constellation Coma Berenices
Right ascension 12h 30m 26.8829s
Declination +22° 52′ 47.383″
Apparent magnitude (V) 8.76
Characteristics
Spectral type G5 V
B−V color index 0.764
V−R color index 0.4
R−I color index 0.4
Variable type ”None”
Astrometry
Radial velocity (Rv) -30.7 km/s
Proper motion (μ) RA: -45.05 mas/yr
Dec.: -105.39 mas/yr
Parallax (π) 14.59 ± 1.24 mas
Distance 220 ± 20 ly
(69 ± 6 pc)
Absolute magnitude (MV) 3.72
Details
Mass 1 M☉
Radius 1.22 R☉
Luminosity 1.14 L☉
Temperature 5407 K
Metallicity [Fe/H]=+0.14
Rotation 37.82 days
Age 7.26 Gyr
Other designations
BD+23°2466, HIP 61028, SAO 82344
Database references
SIMBAD data
NStED data
Extrasolar Planets
Encyclopaedia		 data

HD 108874 is a yellow dwarf star (spectral type G5 V) in the constellation of Coma Berenices. It is 223 light years from Earth and has two extrasolar planets that are possibly in a 4:1 orbital resonance.

Contents

Star

HD 108874 is 2.7 billion years older than our Sun. The star has a temperature of 5407 K and luminosity 1.14 solar. Its metallicity is 1.38 times solar, meaning it has greater iron abundance relative to hydrogen and helium. It has about the same mass as the Sun, but the radius is 22% greater.

Planetary system

In 2003, the jovian planet HD 108874 b was discovered by the US-based team Paul Butler, Geoffrey Marcy, Steven Vogt, and Debra Fischer.[1] This planet receives the amount of insolation closest to Earth of any extrasolar planet. In 2005, further observations revealed this star has another jovian planet orbiting further out, designated as HD 108874 c.[2] Those two planets are in a 4:1 orbital resonance. This means if HD 108874 b orbits the star four times, then HD 108874 c orbits only once, because the orbital period for planet c is four times longer than planet b.

The HD 108874 system[3]
Companion
(in order from star)		 Mass Semimajor axis
(AU)		 Orbital period
(days)		 Eccentricity
b >1.34 ± 0.11 MJ 1.053 ± 0.061 394.48 ± 0.60 0.128 ± 0.022
c >1.064 ± 0.099 MJ 2.77 ± 0.16 1680 ± 24 0.273 ± 0.040

See also

References

  1. ^ Butler, R. Paul et al. (2003). "Seven New Keck Planets Orbiting G and K Dwarfs". The Astrophysical Journal 582 (1): 455–466. Bibcode 2003ApJ...582..455B. doi:10.1086/344570. http://www.iop.org/EJ/article/0004-637X/582/1/455/56131.html. 
  2. ^ Vogt, Steven S. et al. (2005). "Five New Multicomponent Planetary Systems". The Astrophysical Journal 632 (1): 638–658. Bibcode 2005ApJ...632..638V. doi:10.1086/432901. http://iopscience.iop.org/0004-637X/632/1/638/fulltext/. 
  3. ^ Wright et al. (2009). "Ten New and Updated Multi-planet Systems, and a Survey of Exoplanetary Systems" (abstract). The Astrophysical Journal 693 (2): 1084–1099. Bibcode 2009ApJ...693.1084W. doi:10.1088/0004-637X/693/2/1084. http://www.iop.org/EJ/abstract/0004-637X/693/2/1084/. (web Preprint)

External links

Coordinates: 12h 30m 26.8829s, +22° 52′ 47.383″