HD 219828 b

Last updated
HD 219828 b
Discovery
Discovered by Melo et al.
Discovery site Flag of Chile.svg  Chile
Discovery dateFeb 18, 2007
radial velocity
Orbital characteristics
0.052 AU (7,800,000 km)
Eccentricity 0.021
3.8335 ± 0.0013 d
2,453,898.6289 ± 0.072
0
Semi-amplitude 7 ± 50
Star HD 219828

    HD 219828 b is an extrasolar planet approximately 265 light years away in the constellation of Pegasus. This is a Neptune-mass planet at least 21 times more massive than Earth. The planet's composition is unknown, but it may be similar to the ice giants Uranus and Neptune, or alternatively it may be a mainly rocky like Super-Earth. [1]

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    References

    1. Melo, C.; et al. (2007). "A new Neptune-mass planet orbiting HD 219828". Astronomy and Astrophysics. 467 (2): 721–727. arXiv: astro-ph/0702459 . Bibcode:2007A&A...467..721M. doi:10.1051/0004-6361:20066845.

    Coordinates: Jupiter and moon.png 23h 18m 46.7353s, +18° 38′ 44.590″