Epsilon Carinae
Encyclopedia
Epsilon Carinae (ε Car, ε Carinae) is a 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...

 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....

 Carina
Carina (constellation)
Carina is a constellation in the southern sky. Its name is Latin for the keel of a ship, and it was formerly part of the larger constellation of Argo Navis until that constellation was divided in three.-Stars:...

. At apparent 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...

 +1.86 it is one of the brightest stars in the night sky, but is not visible from the northern hemisphere
Northern Hemisphere
The Northern Hemisphere is the half of a planet that is north of its equator—the word hemisphere literally means “half sphere”. It is also that half of the celestial sphere north of the celestial equator...

.

It is also known by the name Avior, but this is not a classical name. It was assigned to the star by Her Majesty's Nautical Almanac Office in the late 1930s during the creation of The Air Almanac, a navigational almanac for the Royal Air Force
Royal Air Force
The Royal Air Force is the aerial warfare service branch of the British Armed Forces. Formed on 1 April 1918, it is the oldest independent air force in the world...

. Of the fifty-seven navigation stars included in the new almanac, two had no classical names: Epsilon Carinae and Alpha Pavonis
Alpha Pavonis
Alpha Pavonis is a star in the constellation Pavo. It is also known by the name Peacock, which was assigned by Her Majesty's Nautical Almanac Office in the late 1930s during the creation of the Air Almanac, a navigational almanac for the Royal Air Force...

. The RAF insisted that all of the stars must have names, so new names were invented. Alpha Pavonis was named "Peacock", a translation of Pavo
Pavo (constellation)
Pavo is a constellation in the southern sky. Its name is Latin for peacock. It is one of twelve constellations created by Petrus Plancius from the observations of Pieter Dirkszoon Keyser and Frederick de Houtman and it first appeared on a 35-cm diameter celestial globe published in 1597 in...

, whilst Epsilon Carinae was called "Avior".

In Chinese
Chinese language
The Chinese language is a language or language family consisting of varieties which are mutually intelligible to varying degrees. Originally the indigenous languages spoken by the Han Chinese in China, it forms one of the branches of Sino-Tibetan family of languages...

, , meaning Sea Rock, refers to an asterism consisting of ε Carinae, ι Carinae
Iota Carinae
Iota Carinae is a star in the constellation Carina. It is one of the brighter stars in the night sky.It has the traditional names Aspidiske, Scutulum and Turais...

, HD 83183
HD 83183
HD 83183, also known as h Carinae is a star in the constellation Carina. It is a blue-white B-type bright giant with an apparent magnitude of +4.08 and is approximately 1980 light years from Earth....

, HD 84810
HD 84810
HD 84810, also known as l Carinae is a star in the constellation Carina.l Carinae is a yellow G-type supergiant with a mean apparent magnitude of +3.69. It is approximately 1510 light years from Earth. It is classified as a Cepheid variable star and its brightness varies from magnitude +3.28 to...

 and υ Carinae
Upsilon Carinae
Upsilon Carinae is a binary star in the constellation Carina. It is part of the Diamond Cross asterism in southern Carina....

  . Consequently, ε Carinae itself is known as

Epsilon Carinae is 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...

 located 630 light years away from the 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...

. The primary component is a dying orange giant of spectral class
Stellar classification
In astronomy, stellar classification is a classification of stars based on their spectral characteristics. The spectral class of a star is a designated class of a star describing the ionization of its chromosphere, what atomic excitations are most prominent in the light, giving an objective measure...

 K0 III, and the secondary is a hot hydrogen
Hydrogen
Hydrogen is the chemical element with atomic number 1. It is represented by the symbol H. With an average atomic weight of , hydrogen is the lightest and most abundant chemical element, constituting roughly 75% of the Universe's chemical elemental mass. Stars in the main sequence are mainly...

-fusing blue dwarf of class B2 V. The stars regularly eclipse
Eclipse
An eclipse is an astronomical event that occurs when an astronomical object is temporarily obscured, either by passing into the shadow of another body or by having another body pass between it and the viewer...

each other, leading to brightness fluctuations on the order of 0.1 magnitudes.
The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
x
OK