HD 83443
Encyclopedia
HD 83443 is an orange dwarf
star approximately 142 light-year
s away in the constellation
of Vela
. As of 2000, at least one extrasolar planet
has been confirmed to be orbiting the star.
was discovered in 2000 by the Geneva Extrasolar Planet Search Team led by Michel Mayor
. It has a minimum mass comparable to Saturn's, and its orbit is one of the shortest known, 1/25th that of Earth
's. It takes only three day
s to complete one revolution around the star. This hot Jupiter
is likely to be slightly larger than Jupiter in radius.
In 2000, the same year that planet b was found, another planet around HD 83443 was announced by the Geneva Team. The new planet was designated as "HD 83443 c". It had a mass smaller than planet b and a short, very eccentric orbit. Its orbital period, 28.9 days, was especially interesting, because it indicated a 10:1 orbital resonance
between the planets. However, a team led by astronomer Paul Butler
did not detect any signal indicating the existence of the second planet. New observations by the Geneva team could not detect the signal either and the discovery claim had to be retracted. The origin of the signal, which was "highly significant" in the earlier data is not yet clear.
Orange dwarf
A K-type main-sequence star , also referred to orange dwarf, are main-sequence stars of spectral type K and luminosity class V. These stars are intermediate in size between red M-type main-sequence stars and yellow G-type main-sequence stars...
star approximately 142 light-year
Light-year
A light-year, also light year or lightyear is a unit of length, equal to just under 10 trillion kilometres...
s away in the constellation
Constellation
In modern astronomy, a constellation is an internationally defined area of the celestial sphere. These areas are grouped around asterisms, patterns formed by prominent stars within apparent proximity to one another on Earth's night sky....
of Vela
Vela (constellation)
Vela is a constellation in the southern sky. Its name is Latin for the sails of a ship, and it was originally part of a larger constellation, the ship Argo Navis, which was later divided into three parts, the others being Carina and Puppis.-Stars:...
. As of 2000, at least one extrasolar planet
Extrasolar planet
An extrasolar planet, or exoplanet, is a planet outside the Solar System. A total of such planets have been identified as of . It is now known that a substantial fraction of stars have planets, including perhaps half of all Sun-like stars...
has been confirmed to be orbiting the star.
Planetary system
The planet HD 83443 bHD 83443 b
HD 83443 b is an extrasolar planet approximately 142 light-years away in the constellation of Vela. It was discovered in 2000 by the Geneva Extrasolar Planet Search Team led by Michel Mayor. It has a minimum mass comparable to Saturn, and its orbit is one of the shortest known, 1/25th that of...
was discovered in 2000 by the Geneva Extrasolar Planet Search Team led by Michel Mayor
Michel Mayor
Dr. Michel G. E. Mayor is a Swiss astrophysicist and professor emeritus at the University of Geneva's Department of Astronomy. He formally retired in 2007, but remains active as a researcher at the Observatory of Geneva...
. It has a minimum mass comparable to Saturn's, and its orbit is one of the shortest known, 1/25th that of Earth
Earth
Earth is the third planet from the Sun, and the densest and fifth-largest of the eight planets in the Solar System. It is also the largest of the Solar System's four terrestrial planets...
's. It takes only three day
Day
A day is a unit of time, commonly defined as an interval equal to 24 hours. It also can mean that portion of the full day during which a location is illuminated by the light of the sun...
s to complete one revolution around the star. This hot Jupiter
Hot Jupiter
Hot Jupiters are a class of extrasolar planet whose mass is close to or exceeds that of Jupiter...
is likely to be slightly larger than Jupiter in radius.
In 2000, the same year that planet b was found, another planet around HD 83443 was announced by the Geneva Team. The new planet was designated as "HD 83443 c". It had a mass smaller than planet b and a short, very eccentric orbit. Its orbital period, 28.9 days, was especially interesting, because it indicated a 10:1 orbital resonance
Orbital resonance
In celestial mechanics, an orbital resonance occurs when two orbiting bodies exert a regular, periodic gravitational influence on each other, usually due to their orbital periods being related by a ratio of two small integers. Orbital resonances greatly enhance the mutual gravitational influence of...
between the planets. However, a team led by astronomer Paul Butler
R. Paul Butler
R. Paul Butler is an astronomer who searches for extrasolar planets.He received a BA and an MS from San Francisco State University, completing a Master's thesis with Geoffrey Marcy, and then completed his doctoral studies at the University of Maryland, College Park in 1993...
did not detect any signal indicating the existence of the second planet. New observations by the Geneva team could not detect the signal either and the discovery claim had to be retracted. The origin of the signal, which was "highly significant" in the earlier data is not yet clear.