Cor Caroli
Encyclopedia
Cor Caroli is the brightest star
in the northern constellation
Canes Venatici
. The name Cor Caroli means Charles' heart, and was named by Sir Charles Scarborough in honour of Charles I
, who was executed in the aftermath of the English Civil War
, and otherwise associated to Charles II of England
, his son, who was restored to the throne after the interregnum
following his father's death.
In Chinese
, , meaning Imperial Guards
, refers to an asterism consisting of α Canum Venaticorum, 10 Canum Venaticorum, β Canum Venaticorum, 6 Canum Venaticorum
, 2 Canum Venaticorum, 67 Ursae Majoris. Consequently, α Canum Venaticorum itself is known as From this Chinese name, the name Chang Chen was appeared.
Cor Caroli is a binary star
with a combined apparent magnitude
of 2.81. The two stars are 19.6 arcseconds apart in the sky and are easily resolved in small telescopes. The system lies approximately 110 light years from Earth
. The brighter of the two stars is designated α² Canum Venaticorum, the fainter α¹ Canum Venaticorum.
Cor Caroli marks the northern vertex of the Diamond of Virgo asterism
.
A0, and has an apparent visual magnitude which varies between 2.84 and 2.98, with a period of 5.47 days. It is a chemically peculiar star with a strong magnetic field, about 5,000 times as strong as the Earth's, and is also classified as an Ap/Bp star. Its atmosphere has overabundances of some elements, such as silicon
, mercury
, and europium
. This is thought to be due to some elements sinking down into the star under the force of gravity while others are elevated by radiation pressure. This star is the prototype of a class of variable star
s, the so-called α² Canum Venaticorum stars. The strong magnetic field
of these stars is believed to produce starspots of enormous extent. Due to these starspots the brightness of α² Canum Venaticorum stars varies considerably during their rotation.
star
. It is considerably fainter than its companion and has an apparent visual magnitude of approximately 5.60.
was a United States Navy
Crater class cargo ship
named after the 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 northern 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....
Canes Venatici
Canes Venatici
Canes Venatici is one of the 88 official modern constellations. It is a small northern constellation that was created by Johannes Hevelius in the 17th century. Its name is Latin for "hunting dogs", and the constellation is often depicted in illustrations as representing the dogs of Boötes the...
. The name Cor Caroli means Charles' heart, and was named by Sir Charles Scarborough in honour of Charles I
Charles I of England
Charles I was King of England, King of Scotland, and King of Ireland from 27 March 1625 until his execution in 1649. Charles engaged in a struggle for power with the Parliament of England, attempting to obtain royal revenue whilst Parliament sought to curb his Royal prerogative which Charles...
, who was executed in the aftermath of the English Civil War
English Civil War
The English Civil War was a series of armed conflicts and political machinations between Parliamentarians and Royalists...
, and otherwise associated to Charles II of England
Charles II of England
Charles II was monarch of the three kingdoms of England, Scotland, and Ireland.Charles II's father, King Charles I, was executed at Whitehall on 30 January 1649, at the climax of the English Civil War...
, his son, who was restored to the throne after the interregnum
Interregnum
An interregnum is a period of discontinuity or "gap" in a government, organization, or social order...
following his father's death.
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 Imperial Guards
Supreme Palace enclosure
Tai Wei Yuan, the Supreme Palace Enclosure , is one of the San Yuan or Three enclosures. Stars and constellations of this group are visible during autumn in the Northern Hemisphere .-Asterisms:The asterisms are :...
, refers to an asterism consisting of α Canum Venaticorum, 10 Canum Venaticorum, β Canum Venaticorum, 6 Canum Venaticorum
6 Canum Venaticorum
6 Canum Venaticorum is a star in the constellation Canes Venatici. It is a yellow G-type giant with an apparent magnitude of +5.01. This star is approximately 227 light years from Earth....
, 2 Canum Venaticorum, 67 Ursae Majoris. Consequently, α Canum Venaticorum itself is known as From this Chinese name, the name Chang Chen was appeared.
Cor Caroli 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...
with a combined 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...
of 2.81. The two stars are 19.6 arcseconds apart in the sky and are easily resolved in small telescopes. The system lies approximately 110 light years from 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 brighter of the two stars is designated α² Canum Venaticorum, the fainter α¹ Canum Venaticorum.
Cor Caroli marks the northern vertex of the Diamond of Virgo asterism
Asterism (astronomy)
In astronomy, an asterism is a pattern of stars recognized on Earth's night sky. It may form part of an official constellation, or be composed of stars from more than one. Like constellations, asterisms are in most cases composed of stars which, while they are visible in the same general direction,...
.
α² Canum Venaticorum
α² Canum Venaticorum has spectral typeStellar 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...
A0, and has an apparent visual magnitude which varies between 2.84 and 2.98, with a period of 5.47 days. It is a chemically peculiar star with a strong magnetic field, about 5,000 times as strong as the Earth's, and is also classified as an Ap/Bp star. Its atmosphere has overabundances of some elements, such as silicon
Silicon
Silicon is a chemical element with the symbol Si and atomic number 14. A tetravalent metalloid, it is less reactive than its chemical analog carbon, the nonmetal directly above it in the periodic table, but more reactive than germanium, the metalloid directly below it in the table...
, mercury
Mercury (element)
Mercury is a chemical element with the symbol Hg and atomic number 80. It is also known as quicksilver or hydrargyrum...
, and europium
Europium
Europium is a chemical element with the symbol Eu and atomic number 63. It is named after the continent of Europe. It is a moderately hard silvery metal which readily oxidizes in air and water...
. This is thought to be due to some elements sinking down into the star under the force of gravity while others are elevated by radiation pressure. This star is the prototype of a class of variable star
Variable star
A star is classified as variable if its apparent magnitude as seen from Earth changes over time, whether the changes are due to variations in the star's actual luminosity, or to variations in the amount of the star's light that is blocked from reaching Earth...
s, the so-called α² Canum Venaticorum stars. The strong magnetic field
Magnetic field
A magnetic field is a mathematical description of the magnetic influence of electric currents and magnetic materials. The magnetic field at any given point is specified by both a direction and a magnitude ; as such it is a vector field.Technically, a magnetic field is a pseudo vector;...
of these stars is believed to produce starspots of enormous extent. Due to these starspots the brightness of α² Canum Venaticorum stars varies considerably during their rotation.
α¹ Canum Venaticorum
α1 Canum Venaticorum is a F-type main sequenceMain sequence
The main sequence is a continuous and distinctive band of stars that appears on plots of stellar color versus brightness. These color-magnitude plots are known as Hertzsprung–Russell diagrams after their co-developers, Ejnar Hertzsprung and Henry Norris Russell...
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...
. It is considerably fainter than its companion and has an apparent visual magnitude of approximately 5.60.
Namesakes
USS Cor Caroli (AK-91)USS Cor Caroli (AK-91)
USS Cor Caroli was an Crater-class cargo ship commissioned by the U.S. Navy for service in World War II, named after Cor Caroli, the brightest star in constellation Canes Venatici. She was responsible for delivering goods and equipment to locations in the war zone.Cor Caroli was launched 19 March...
was a United States Navy
United States Navy
The United States Navy is the naval warfare service branch of the United States Armed Forces and one of the seven uniformed services of the United States. The U.S. Navy is the largest in the world; its battle fleet tonnage is greater than that of the next 13 largest navies combined. The U.S...
Crater class cargo ship
Crater class cargo ship
Crater-class cargo ship is a category of freighter that was constructed for use by the United States Navy during World War II under Maritime Commission EC2-S-C1 type....
named after the star.