Omicron Puppis (ο Puppis) is candidate

binary star A binary star or binary star system is a system of two stars that are gravitationally bound to and in orbit around each other. Binary stars in the night sky that are seen as a single object to the naked eye are often resolved as separate stars us ...

system 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 ...

Puppis Puppis ("poop deck, stern") is a constellation in the southern sky. It was originally part of the Former constellations, traditional constellation of Argo Navis (the ship of Jason and the Argonauts), which was divided into three parts, the other ...

. It is visible to the naked eye, having a combined

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 +4.48. Based upon an annual parallax shift of 2.30 mas as seen from Earth, it is located roughly 1,400

light year A light-year, alternatively spelled light year (ly or lyr), is a unit of length used to express astronomical distance, astronomical distances and is equal to exactly , which is approximately 9.46 trillion km or 5.88 trillion mi. As defined by t ...

s from the Sun. This is a suspected close

spectroscopic binary A binary star or binary star system is a system of two stars that are gravitationally bound to and in orbit around each other. Binary stars in the night sky that are seen as a single object to the naked eye are often resolved as separate stars us ...

system. The

spectrum A spectrum (: spectra or spectrums) is a set of related ideas, objects, or properties whose features overlap such that they blend to form a continuum. The word ''spectrum'' was first used scientifically in optics to describe the rainbow of co ...

varies with a periodicity of 28.9 days, and a helium emission component shows a

radial velocity The radial velocity or line-of-sight velocity of a target with respect to an observer is the rate of change of the vector displacement between the two points. It is formulated as the vector projection of the target-observer relative velocity ...

variation that matches the period. The properties indicate it may be a φ Per-like system with a

Be star Be stars are a heterogeneous set of stars with B spectral types and emission lines. A narrower definition, sometimes referred to as ''classical Be stars'', is a non-supergiant B star whose spectrum has, or had at some time, one or more Balmer ...

primary and a hot subdwarf companion of type sdO. If this is the case, then the pair have a circular orbit with a period that matches the variability. The close-orbiting pair may have undergone interaction in the past, leaving the subdwarf stripped down and the primary star spinning rapidly. OmiPupLightCurve

ο Puppis is slightly variable. The

General Catalogue of Variable Stars The General Catalogue of Variable Stars (GCVS) is a list of variable stars in the Milky Way Galaxy. Its first edition, containing 10,820 stars, was published in 1948 by the Academy of Sciences of the USSR, edited by and Pavel Parenago. Second a ...

lists it as a possible

with a magnitude range of 4.43 - 4.46. The International Variable Star Index classifies it as a

Lambda Eridani variable A Lambda Eridani Variable is a class of Be stars that show small amplitude variations of a few hundredths of a magnitude. The variations are highly regular with periods between 0.5 and 2.0 days, and they were initially described as periodic Be star ...

Naming

The correct

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 ...

for ο Puppis has been debated. Lacaille assigned one Greek letter sequence for the bright stars of

Argo Navis Argo Navis (the Ship Argo), or simply Argo, is one of Ptolemy's 48 constellations, now a grouping of three IAU constellations. It is formerly a single large constellation in the southern sky. The genitive is "Argus Navis", abbreviated "Arg". ...

. These Lacaille designations are now shared across the three modern constellations of

Carina Carina may refer to: Places Australia * Carina, Queensland, a suburb in Brisbane * Carina Heights, Queensland, a suburb in Brisbane * Carina, Victoria, a locality in Mildura Serbia * Carina, Osečina, a village in the Kolubara District ...

, and Vela so that (except for omicron) each Greek letter is found in only one of the three. However, ο (omicron) is now commonly used for two stars, one each in Vela and Puppis. In the ''Coelum Australe Stelliferum'' itself, this star is labelled (Latin) o Argus in puppi (''Pouppe du Navire'' in the French edition), while ο Velorum is labelled ο (omicron) Argus (''du Navire'' in the French edition). Some later authors state the reverse, that Lacaille actually assigned omicron to ο Puppis and Latin lower case 'o' to ο Velorum. Modern catalogs and atlases generally use omicron for both stars. In Chinese, (), meaning ''

Bow and Arrow The bow and arrow is a ranged weapon system consisting of an elasticity (physics), elastic launching device (bow) and long-shafted projectiles (arrows). Humans used bows and arrows for hunting and aggression long before recorded history, and the ...

'', refers to an asterism consisting of ο Puppis, δ Canis Majoris, η Canis Majoris, HD 63032, HD 65456, k Puppis, ε Canis Majoris, κ Canis Majoris and π Puppis. Consequently, ο Puppis itself is known as (, .)AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 7 月 17 日

References

{{DEFAULTSORT:Omicron Puppis B-type subgiants Lambda Eridani variables Be stars Puppis, Omicron Puppis Durchmusterung objects 063462 038070 3045