HD 69830 d

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HD 69830 d
Extrasolar planet List of extrasolar planets
HD 69830 and HD 69830 d.png
HD 69830 and HD 69830 d
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) 0.63 AU
Eccentricity (e) 0.07 ± 0.07
Orbital period (P) 197 ± 3 d
Argument of
periastron
(ω) 224 ± 61°
Time of periastron (T0) 24513358 ± 34 JD
Semi-amplitude (K) 2.20 ± 0.19 m/s
Physical characteristics
Minimum mass (m sin i) 0.058 MJ
Temperature (T) ~284 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 d is an exoplanet orbiting the K-type main-sequence star HD 69830 every 197 days. It is the outermost known planet in its planetary system and possibly lies within its habitable zone.

Discovery[edit]

HD 69830 d was discovered in 2006 with the HARPS echelle spectrograph installed on the European Southern Observatory 3.6-meter telescope at La Silla Observatory, Chile.[2]

Orbit and mass[edit]

The planet's orbit has a low orbital eccentricity, like most of the planets in the Solar System. The semimajor axis of the orbit is only 0.63 AU, similar to that of Venus. However, its star is less massive and energetic than the Sun, thereby putting the planet within its habitable zone. It is 17 times the mass of the Earth, and 42 light-years from the Solar System.[3]

Characteristics[edit]

HD 69830 has around the mass of Neptune, and hence it is likely that HD 69830 d is gaseous with no solid surface. Because it has only been detected indirectly through its gravitational effects on its star, properties such as its radius and composition are unknown.

Popular culture references[edit]

  • In the Bestiarum included with the special editions of Halo 3, HD 69830 is described as the home star of the Jackals, specifically stating that they come from a hypothetical moon of the third planet at the inner edge of the asteroid belt.
  • It is mentioned as a potentially habitable planet on the History Channel´s program The Universe.

See also[edit]

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. PMID 16710412. 
  3. ^ "The Universe ("Another Earth")". H2. January 13, 2009. 

External links[edit]

Coordinates: Sky map 08h 18m 23.9s, −12° 37′ 55.0″