81 Ceti b (abbreviated 81 Cet b) is an
extrasolar planet
An exoplanet or extrasolar planet is a planet outside the Solar System. The first confirmed detection of an exoplanet was in 1992 around a pulsar, and the first detection around a main-sequence star was in 1995. A different planet, first detect ...
approximately 331
light year
A light-year, alternatively spelled light year (ly or lyr), is a unit of length used to express astronomical distance, astronomical distances and is equal to exactly , which is approximately 9.46 trillion km or 5.88 trillion mi. As defined by t ...
s away in the
constellation
A constellation is an area on the celestial sphere in which a group of visible stars forms Asterism (astronomy), a perceived pattern or outline, typically representing an animal, mythological subject, or inanimate object.
The first constellati ...
of
Cetus
Cetus () is a constellation, sometimes called 'the whale' in English. The Cetus (mythology), Cetus was a sea monster in Greek mythology which both Perseus and Heracles needed to slay. Cetus is in the region of the sky that contains other water- ...
. It is estimated to be 5.3 times the mass of Jupiter which also makes it a gas giant.
It orbits the
K-type giant star
A giant star has a substantially larger radius and luminosity than a main-sequence (or ''dwarf'') star of the same surface temperature. They lie above the main sequence (luminosity class V in the Yerkes spectral classification) on the Hertzsp ...
81 Ceti at an average distance of 2.5
AU, taking about 2.6 years to revolve with an
eccentricity
Eccentricity or eccentric may refer to:
* Eccentricity (behavior), odd behavior on the part of a person, as opposed to being "normal"
Mathematics, science and technology Mathematics
* Off-Centre (geometry), center, in geometry
* Eccentricity (g ...
of 0.206.
Discovery
The preprint announcing this planet was submitted to the
arXiv
arXiv (pronounced as "archive"—the X represents the Chi (letter), Greek letter chi ⟨χ⟩) is an open-access repository of electronic preprints and postprints (known as e-prints) approved for posting after moderation, but not Scholarly pee ...
electronic repository on July 2, 2008, by Bun'ei Sato and collaborators, who discovered it using the
Doppler Spectroscopy
Doppler spectroscopy (also known as the radial-velocity method, or colloquially, the wobble method) is an indirect method for finding extrasolar planets and brown dwarfs from radial-velocity measurements via observation of Doppler shifts in ...
method, during the
Okayama Planet Search
is the prefectural capital, capital Cities of Japan, city of Okayama Prefecture in the Chūgoku region of Japan. The Okayama metropolitan area, centered around the city, has the largest urban employment zone in the Chugoku region of western J ...
radial velocity survey of G and K giants at
Okayama Astrophysical Observatory
The (NAOJ) is an astronomy, astronomical research organisation comprising several facilities in Japan, as well as an observatory in Hawaii and Chile. It was established in 1988 as an amalgamation of three existing research organizations - the To ...
.
See also
*
14 Andromedae b
*
6 Lyncis b
6 Lyncis b (abbreviated 6 Lyn b) is an extrasolar planet orbiting the K-type subgiant star 6 Lyncis which is approximately 182 light years away in the Lynx constellation. The planet has a minimum mass . The orbital period for this planet is 899 ...
*
79 Ceti b
*
94 Ceti b
References
External links
*
*
Cetus
Giant planets
Exoplanets discovered in 2008
Exoplanets detected by radial velocity
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