) Lambda Velorum (λ Velorum, abbreviated Lambda Vel, λ Vel), officially named Suhail , is a star in the southern constellation of Vela. With a mean

apparent visual magnitude Apparent magnitude () is a measure of the brightness of a star or other astronomical object observed from Earth. An object's apparent magnitude depends on its intrinsic luminosity, its distance from Earth, and any extinction of the object's lig ...

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 technique, yielding an estimated from the

Sun The Sun is the star at the center of the Solar System. It is a nearly perfect ball of hot plasma, heated to incandescence by nuclear fusion reactions in its core. The Sun radiates this energy mainly as light, ultraviolet, and infrared radi ...

Nomenclature

''λ Velorum'' ( Latinised to ''Lambda Velorum'') is the star's Bayer designation. It bore the traditional

Arabic Arabic (, ' ; , ' or ) is a Semitic language spoken primarily across the Arab world.Semitic languages: an international handbook / edited by Stefan Weninger; in collaboration with Geoffrey Khan, Michael P. Streck, Janet C. E.Watson; Walter ...

name السهيل الوزن ''suhayl al-wazn'' (''Al 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 and the second-brightest star in the night sky. It is also designated α Carinae, which is Latinised to Alpha Carinae. With a visual apparent magnitude ...

;

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 +1.7, it is one of t ...

(al Suhail al Muhlif); and

Zeta Puppis Zeta Puppis (ζ Puppis, abbreviated Zeta Pup, ζ Pup), formally named Naos , is a star in the constellation of Puppis. The spectral type, 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; french: link=yes, Union astronomique internationale, UAI) is a nongovernmental organisation with the objective of advancing astronomy in all aspects, including promoting astronomical research, outreac ...

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 Chinese people have identified stars from 1300 BCE, as Chinese star names later categorized in the twe ...

, Suhail is called 天記 (

Pinyin Hanyu Pinyin (), often shortened to just pinyin, is the official romanization system for Standard Chinese, Standard Mandarin Chinese in China, and to some extent, in Singapore and Malaysia. It is often used to teach Mandarin, normally writte ...

: 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 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 Psi Velorum, Romanization of Greek, Latinized from ψ Velorum, is a binary star system in the southern constellation of Vela (constellation), Vela. Based upon an annual stellar parallax, parallax shift of 53.15 milliarcsecond, mas a ...

by R. H. Allen works and the meaning is "Heaven's Record".

Properties

The outer envelope of λ Velorum has an effective 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 with time. This variation may be caused by a change in emitted light or by something partly blocking the light, so variable stars are classified as e ...

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

evolved Evolution is change in the heritable characteristics of biological populations over successive generations. These characteristics are the expressions of genes, which are passed on from parent to offspring during reproduction. Variation ...

star that has exhausted the hydrogen in its core region. It has about seven times the mass of the Sun. It is likely to be on or approaching the asymptotic giant branch (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 sta ...

(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 due to 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. 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 (PN, plural PNe) 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 unrelate ...

and a

white dwarf A white dwarf is a stellar core remnant composed mostly of electron-degenerate matter. A white dwarf is very dense: its mass is comparable to the Sun's, while its volume is comparable to the Earth's. A white dwarf's faint luminosity comes ...

remnant. It may be massive enough to produce an electron-capture supernova.

References

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