HD 142
Encyclopedia
HD 142 is a 6th magnitude
Apparent magnitude
The apparent magnitude of a celestial body is a measure of its brightness as seen by an observer on Earth, adjusted to the value it would have in the absence of the atmosphere...

 star
Star
A star is a massive, luminous sphere of plasma held together by gravity. At the end of its lifetime, a star can also contain a proportion of degenerate matter. The nearest star to Earth is the Sun, which is the source of most of the energy on Earth...

 approximately 84 light years 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 Phoenix
Phoenix (constellation)
Phoenix is a minor constellation in the southern sky. It is named after the Phoenix, a mythical bird. It is faint: there are only two stars in the whole constellation which are brighter than magnitude 5.0...

. A companion star was detected in 1894 making this a binary star
Binary star
A binary star is a star system consisting of two stars orbiting around their common center of mass. The brighter star is called the primary and the other is its companion star, comes, or secondary...

 system.

Planetary system

In 2001, the Anglo-Australian Planet Search
Anglo-Australian Planet Search
The Anglo-Australian Planet Search or AAPS is a long-term astronomical survey started in 1998 and continuing to the present. It is being carried out on the 3.9m Anglo-Australian Telescope, AAT, of the Anglo-Australian Observatory in Australia. The purpose of this survey is to catalog planets around...

 team led by Chris Tinney
Chris Tinney
Chris Tinney is an astronomer at the University of New South Wales who is focused on extrasolar planet and brown dwarf research. He is a member of the Anglo-Australian Planet Search team which has discovered over twenty planets by doppler spectroscopy. He is also the former head of astronomy at the...

 announced the discovery of an 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...

 orbiting the star. There is an additional linear trend in the radial velocity
Radial velocity
Radial velocity is the velocity of an object in the direction of the line of sight . In astronomy, radial velocity most commonly refers to the spectroscopic radial velocity...

 data that may be due to another planet or to the stellar companion.
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