3 Centauri
Encyclopedia
3 Centauri is a binary star
in the constellation
Centaurus
. It is approximately 298 light years from Earth
.
The primary component, 3 Centauri A, is a blue-white B-type
giant
with a mean apparent magnitude
of +4.56. It is a variable star
, and its brightness varies from magnitude +4.27 to +4.32 It is suspected the variations in luminosity are a result of the primary being an eclipsing binary, which would mean the system would consist of at least three objects. Its more distant companion, 3 Centauri B, is located 7.9 arcseconds away. It is a blue-white B-type main sequence dwarf
and has an apparent magnitude of +6.06.
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...
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....
Centaurus
Centaurus
Centaurus is a bright constellation in the southern sky. One of the largest constellations, Centaurus was included among the 48 constellations listed by the 2nd century astronomer Ptolemy, and it remains one of the 88 modern constellations.-Stars:...
. It is approximately 298 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 primary component, 3 Centauri A, is a blue-white B-type
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...
giant
Giant star
A giant star is a star with substantially larger radius and luminosity than a main sequence star of the same surface temperature. Typically, giant stars have radii between 10 and 100 solar radii and luminosities between 10 and 1,000 times that of the Sun. Stars still more luminous than giants are...
with a mean 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 +4.56. It is a 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...
, and its brightness varies from magnitude +4.27 to +4.32 It is suspected the variations in luminosity are a result of the primary being an eclipsing binary, which would mean the system would consist of at least three objects. Its more distant companion, 3 Centauri B, is located 7.9 arcseconds away. It is a blue-white B-type main sequence dwarf
Main 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...
and has an apparent magnitude of +6.06.