HD 69830 b

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HD 69830 b
Extrasolar planet List of extrasolar planets
HD 69830 + b.jpg
HD 69830 b looking at its star.
(Artist's impression)
Parent star
Star HD 69830
Constellation Puppis
Right ascension (α) 08h 18m 23.947s[1]
Declination (δ) −12° 37′ 55.81″[1]
Apparent magnitude (mV) 5.95
Distance 40.7 ± 0.2[1] ly
(12.49 ± 0.05[1] pc)
Spectral type K0V
Mass (m) 0.86 ± 0.03 M
Radius (r) 0.89 R
Temperature (T) 5385 ± 20 K
Metallicity [Fe/H] −0.05 ± 0.02
Age 5.1–6.1 Gyr
Orbital elements
Semimajor axis (a) 0.0785 AU
Eccentricity (e) 0.1 ± 0.04
Orbital period (P) 8.667 ± 0.003 d
Argument of
periastron
(ω) 340 ± 26°
Time of periastron (T0) 2,453,496.8 ± 0.06 JD
Semi-amplitude (K) 3.51 ± 0.15 m/s
Physical characteristics
Minimum mass (m sin i) 0.033 MJ
Temperature (T) ~804 K
Discovery information
Discovery date May 18, 2006
Discoverer(s) Lovis et al.[2]
Discovery method Radial velocity
Discovery status Published[2]
Database references
Extrasolar Planets
Encyclopaedia
data
SIMBAD data

HD 69830 b is a Neptune-mass or super-Earth-mass exoplanet orbiting the star HD 69830. It is 10 times more massive than Earth, making it the least massive known exoplanet in the system. It also orbits very close to its parent star and takes 82/3 days to complete an orbit.

This is likely to be a rocky planet, not a gas giant.[2] If it had formed as a gas giant, it would have stayed that way.[3]

If HD 69830 b is a terrestrial planet, models predict that tidal heating would produce a heat flux at the surface of about 55 W/m2. This is 20 times that of Io.[4]

References[edit]

  1. ^ a b c d van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics 474 (2): 653–664. arXiv:0708.1752. Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357. Vizier catalog entry
  2. ^ a b c Lovis, Christophe et al. (2006). "An extrasolar planetary system with three Neptune-mass planets" (PDF). Nature 441 (7091): 305–309. arXiv:astro-ph/0703024. Bibcode:2006Natur.441..305L. doi:10.1038/nature04828. 
  3. ^ H. Lammer et al. (2007). "The impact of nonthermal loss processes on planet masses from Neptunes to Jupiters". Geophysical Research Abstracts 9 (07850). 
  4. ^ Jackson, Brian; Richard Greenberg; Rory Barnes (2008). "Tidal Heating of Extra-Solar Planets". ApJ 681 (2): 1631. arXiv:0803.0026. Bibcode:2008ApJ...681.1631J. doi:10.1086/587641. 

Coordinates: Sky map 08h 18m 23.9s, −12° 37′ 55.8″