Epsilon Leonis (ε Leo, ε Leonis) is the fifth-brightest

star A star is a luminous spheroid of plasma (physics), plasma held together by Self-gravitation, self-gravity. The List of nearest stars and brown dwarfs, nearest star to Earth is the Sun. Many other stars are visible to the naked eye at night sk ...

in the

constellation A constellation is an area on the celestial sphere in which a group of visible stars forms Asterism (astronomy), a perceived pattern or outline, typically representing an animal, mythological subject, or inanimate object. The first constellati ...

Leo, consistent with its

Bayer designation A Bayer designation is a stellar designation in which a specific star is identified by a Greek alphabet, Greek or Latin letter followed by the genitive case, genitive form of its parent constellation's Latin name. The original list of Bayer design ...

Epsilon. It is known as Algenubi or Ras Elased Australis. Both names mean "the southern star of the lion's head". Australis is Latin for "southern" and Genubi is Arabic for "south".

Properties

Epsilon Leonis has a

stellar classification In astronomy, stellar classification is the classification of stars based on their stellar spectrum, spectral characteristics. Electromagnetic radiation from the star is analyzed by splitting it with a Prism (optics), prism or diffraction gratin ...

of G1 II, with the

luminosity class In astronomy, stellar classification is the classification of stars based on their stellar spectrum, spectral characteristics. Electromagnetic radiation from the star is analyzed by splitting it with a Prism (optics), prism or diffraction gratin ...

of II indicating that, it has

evolved Evolution is the change in the heritable Phenotypic trait, characteristics of biological populations over successive generations. It occurs when evolutionary processes such as natural selection and genetic drift act on genetic variation, re ...

into a bright giant. It is much larger and brighter than the Sun with a luminosity 282 times and a radius 21 times solar. Consequently, its absolute magnitude is actually –1.49, making it one of the more luminous stars in the constellation, significantly more than

Regulus Regulus is the brightest object in the constellation Leo (constellation), Leo and one of the List of brightest stars, brightest stars in the night sky. It has the Bayer designation designated α Leonis, which is Latinisation of names, ...

. Its

apparent brightness Apparent magnitude () is a measure of the brightness of a star, astronomical object or other celestial objects like artificial satellites. Its value depends on its intrinsic luminosity, its distance, and any extinction of the object's light cau ...

, though, is only 2.98. Given its distance of about , the star is more than three times the distance from the Sun than Regulus. At this distance, the

visual magnitude Apparent magnitude () is a measure of the brightness of a star, astronomical object or other celestial objects like artificial satellites. Its value depends on its intrinsic luminosity, its distance, and any extinction of the object's light ca ...

of Epsilon Leonis is reduced by 0.03 as a result of

extinction Extinction is the termination of an organism by the death of its Endling, last member. A taxon may become Functional extinction, functionally extinct before the death of its last member if it loses the capacity to Reproduction, reproduce and ...

caused by intervening gas and dust. Epsilon Leonis exhibits the characteristics of a Cepheid-like variable, changing by an amplitude of 0.3 magnitude every few days. It has around four times the mass of the Sun and a

projected rotational velocity Stellar rotation is the angular motion of a star about its axis. The rate of rotation can be measured from the spectrum of the star, or by timing the movements of active features on the surface. The rotation of a star produces an equatorial bu ...

of . Based upon its iron abundance, the

metallicity In astronomy, metallicity is the Abundance of the chemical elements, abundance of Chemical element, elements present in an object that are heavier than hydrogen and helium. Most of the normal currently detectable (i.e. non-Dark matter, dark) matt ...

of this star's outer atmosphere is only around 52% of the Sun's. That is, the abundance of elements other than hydrogen and helium is about half that in the Sun.

References

{{DEFAULTSORT:Epsilon Leonis Leo (constellation) Leonis, Epsilon Algenubi Leonis, 17 Classical Cepheid variables G-type bright giants 047908 3873 084441 Suspected variables Durchmusterung objects

External Links

Go Astronomy Epsilon leonis

Properties

See also

References

External Links