) Lambda Velorum (λ Velorum, abbreviated Lambda Vel, λ Vel), officially named Suhail , is a

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 southern

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 ...

of Vela. With a mean

apparent 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 2.21, this is the third-brightest star in the constellation and one of the brighter stars in the sky. The distance to this star can be measured directly using the

parallax Parallax is a displacement or difference in the apparent position of an object viewed along two different sightline, lines of sight and is measured by the angle or half-angle of inclination between those two lines. Due to perspective (graphica ...

technique, yielding an estimated from the

Sun The Sun is the star at the centre of the Solar System. It is a massive, nearly perfect sphere of hot plasma, heated to incandescence by nuclear fusion reactions in its core, radiating the energy from its surface mainly as visible light a ...

Nomenclature

''λ Velorum'' ( Latinised to ''Lambda Velorum'') is the star's

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 ...

. It bore the traditional

Arabic Arabic (, , or , ) is a Central Semitic languages, Central Semitic language of the Afroasiatic languages, Afroasiatic language family spoken primarily in the Arab world. The International Organization for Standardization (ISO) assigns lang ...

name سهيل الوزن ''Suhail al Wazn'', but as a modern navigation star this was shortened to ''Suhail''. ' Suhail' (a common Arabic male first name) was traditionally used for at least three other stars:

Canopus Canopus is the brightest star in the southern constellation of Carina (constellation), Carina and the list of brightest stars, second-brightest star in the night sky. It is also Bayer designation, designated α Carinae, which is Rom ...

;

Gamma Velorum Gamma Velorum is a quadruple star system in the constellation Vela. This name is the Bayer designation for the star, which is Latinised from γ Velorum and abbreviated γ Vel. At a combined magnitude of +1.72, it is one of the brighte ...

(Suhail al Muhlif); and

Zeta Puppis Zeta Puppis (ζ Puppis, abbreviated Zeta Pup, ζ Pup), formally named Naos , is the brightest star in the constellation of Puppis. The spectral class of O4 means this is one of the hottest, and most luminous, stars ...

(Suhail Hadar). In 2016, the

International Astronomical Union The International Astronomical Union (IAU; , UAI) is an international non-governmental organization (INGO) with the objective of advancing astronomy in all aspects, including promoting astronomical research, outreach, education, and developmen ...

organized a

Working Group on Star Names The International Astronomical Union (IAU) established a Working Group on Star Names (WGSN) in May 2016 to catalog and standardize proper names for stars for the international astronomical community. It operates under Division C – Education ...

(WGSN) to catalogue and standardize proper names for stars. The WGSN approved the name ''Suhail'' for this star on 21 August 2016 and it is now so entered in the IAU Catalog of Star Names (''Canopus'' had its name approved as is, and Zeta Puppis was given the name ''Naos''). In

Chinese astronomy Astronomy in China has a long history stretching from the Shang dynasty, being refined over a period of more than 3,000 years. The Ancient China, ancient Chinese people have identified stars from 1300 BCE, as Chinese star names later categori ...

, Suhail is called 天記 (

Pinyin Hanyu Pinyin, or simply pinyin, officially the Chinese Phonetic Alphabet, is the most common romanization system for Standard Chinese. ''Hanyu'' () literally means 'Han Chinese, Han language'—that is, the Chinese language—while ''pinyin' ...

: Tiānjì), meaning ''Judge for Estimating the Age of Animals'', because this star is marking itself and stands alone in the ''Judge for Estimating the Age of Animals'' asterism.

Ghost In folklore, a ghost is the soul or Spirit (supernatural entity), spirit of a dead Human, person or non-human animal that is believed by some people to be able to appear to the living. In ghostlore, descriptions of ghosts vary widely, from a ...

mansion (see:

Chinese constellation Traditional Chinese astronomy has a system of dividing the celestial sphere into asterisms or constellations, known as "officials" ( Chinese ''xīng guān''). The Chinese asterisms are generally smaller than the constellations of Hellenisti ...

), 天記 (Tiānjì), was westernized into ''Tseen Ke'', but the name ''Tseen Ke'' was designated for Psi Velorum by R. H. Allen works and the meaning is "Heaven's Record".

Properties

It has an

spectral classification ''Spectral'' is a 2016 Hungarian-American military science fiction action film co-written and directed by Nic Mathieu. Written with Ian Fried & George Nolfi, the film stars James Badge Dale as DARPA research scientist Mark Clyne, with Max M ...

of K4 Ib, 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 ...

Ib meaning that it is a lower luminosity

red supergiant Red supergiants (RSGs) are stars with a supergiant luminosity class ( Yerkes class I) and a stellar classification K or M. They are the largest stars in the universe in terms of volume, although they are not the most massive or luminous. Betelg ...

star. The outer envelope of λ Velorum has an

effective temperature The effective temperature of a body such as a star or planet is the temperature of a black body that would emit the same total amount of electromagnetic radiation. Effective temperature is often used as an estimate of a body's surface temperature ...

of about , giving it the cool orange hue of a

K-type star In astronomy, stellar classification is the classification of stars based on their spectral characteristics. Electromagnetic radiation from the star is analyzed by splitting it with a prism or diffraction grating into a spectrum exhibiting the ...

. It is an Lc-type, slow irregular

variable star A variable star is a star whose brightness as seen from Earth (its apparent magnitude) changes systematically with time. This variation may be caused by a change in emitted light or by something partly blocking the light, so variable stars are ...

with its brightness varying between apparent magnitudes +2.14 to +2.30. λ Velorum is an

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 ...

star that has exhausted the hydrogen in its core region. It has about seven times the mass of the Sun. Despite having the luminosity class of a red

supergiant Supergiants are among the most massive and most luminous stars. Supergiant stars occupy the top region of the Hertzsprung–Russell diagram, with absolute visual magnitudes between about −3 and −8. The temperatures of supergiant stars range ...

star, it is likely to be on or approaching the

asymptotic giant branch The asymptotic giant branch (AGB) is a region of the Hertzsprung–Russell diagram populated by evolved cool luminous stars. This is a period of stellar evolution undertaken by all low- to intermediate-mass stars (about 0.5 to 8 solar masses) lat ...

(AGB), although its properties do not exclude it being a slightly more massive star on the

red giant branch The red-giant branch (RGB), sometimes called the first giant branch, is the portion of the giant branch before helium ignition occurs in the course of stellar evolution. It is a stage that follows the main sequence for low- to intermediate-mass st ...

(RGB). As an AGB star it has an inert core of carbon and oxygen and is alternately fusing helium and hydrogen in two shells outside the core. The star's outer envelope has expanded to form a deep,

convective Convection is single or multiphase fluid flow that occurs spontaneously through the combined effects of material property heterogeneity and body forces on a fluid, most commonly density and gravity (see buoyancy). When the cause of the convec ...

, hydrogen-burning layer that is generating a

magnetic field A magnetic field (sometimes called B-field) is a physical field that describes the magnetic influence on moving electric charges, electric currents, and magnetic materials. A moving charge in a magnetic field experiences a force perpendicular ...

. The surface strength of this field has been measured at . Massive stars use their hydrogen "fuel" much faster than do smaller stars and Lambda Velorum is estimated to be only some 32 million years old. λ Velorum is near the upper end of the mass range for intermediate stars, which end their lives by producing a

planetary nebula A planetary nebula is a type of emission nebula consisting of an expanding, glowing shell of ionized gas ejected from red giant stars late in their lives. The term "planetary nebula" is a misnomer because they are unrelated to planets. The ...

and a

white dwarf A white dwarf is a Compact star, stellar core remnant composed mostly of electron-degenerate matter. A white dwarf is very density, dense: in an Earth sized volume, it packs a mass that is comparable to the Sun. No nuclear fusion takes place i ...

remnant. It may be massive enough to produce an

electron-capture Electron capture (K-electron capture, also K-capture, or L-electron capture, L-capture) is a process in which the proton-rich nucleus of an electrically neutral atom absorbs an inner atomic electron, usually from the K or L electron shells. Thi ...

supernova A supernova (: supernovae or supernovas) is a powerful and luminous explosion of a star. A supernova occurs during the last stellar evolution, evolutionary stages of a massive star, or when a white dwarf is triggered into runaway nuclear fusion ...

(like the supernova that formed the

Crab Nebula The Crab Nebula (catalogue designations M1, NGC 1952, Taurus A) is a supernova remnant and pulsar wind nebula in the constellation of Taurus (constellation), Taurus. The common name comes from a drawing that somewhat resembled a crab with arm ...

), and hence a

neutron star A neutron star is the gravitationally collapsed Stellar core, core of a massive supergiant star. It results from the supernova explosion of a stellar evolution#Massive star, massive star—combined with gravitational collapse—that compresses ...

References

{{DEFAULTSORT:Lambda Velorum K-type supergiants Vela (constellation) Velorum, Lambda Durchmusterung objects 078647 044816 3634 Suhail TIC objects Slow irregular variables