Rho Puppis (ρ Puppis, abbreviated Rho Pup, ρ Pup), formally named Tureis , is a star in the southern constellation of Puppis. With an average

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 2.78, it is the third-brightest member of this generally faint constellation. Based upon parallax measurements made during the Hipparcos mission, Rho Puppis is located at a distance of 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 ...

. It is the prototype of the ρ Puppis class of evolved

Am star An Am star or metallic-line star is a type of chemically peculiar star of spectral type A whose spectrum has strong and often variable absorption lines of metals such as zinc, strontium, zirconium, and barium, and deficiencies of others, such as ca ...

Nomenclature

''ρ Puppis'' ( Latinised to ''Rho Puppis'') is the star's Bayer designation. It bore the traditional name ''Tureis'' or ''Turais'', from the

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 ...

''تُرَيْس'' ''turays'' "shield" ( diminutive), which was shared by

Iota Carinae Iota Carinae (ι Carinae, abbreviated Iota Car, ι Car), officially named Aspidiske , is a star in the southern constellation of Carina. With an apparent visual magnitude of 2.2, it is one of the brighter stars in the night sky. Appe ...

. 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 ''Tureis'' for this star on 12 September 2016 and it is now so entered in the IAU Catalog of Star Names (Iota Carinae was given the name ''Aspidiske'' on 20 July 2016).

Properties

At present Rho Puppis is moving away from the Sun with a radial velocity of +46.1 km s⁻¹. The closest approach occurred about 394,000 years ago when it came within roughly of the

Solar System The Solar System Capitalization of the name varies. The International Astronomical Union, the authoritative body regarding astronomical nomenclature, specifies capitalizing the names of all individual astronomical objects but uses mixed "Solar ...

; about the same distance as

Procyon Procyon () is the brightest star in the constellation of Canis Minor and usually the eighth-brightest star in the night sky, with an apparent visual magnitude of 0.34. It has the Bayer designation α Canis Minoris, which is Latinized ...

in the present era. The variability of this star was announced in 1956 by American astronomer Olin J. Eggen. It was determined to be a

Delta Scuti Delta Scuti, Latinized from δ Scuti, is a variable star in the southern constellation Scutum. With an apparent visual magnitude that fluctuates around 4.72, it is the fifth-brightest star in this small and otherwise undistinguished c ...

-type variable star, making it one of the first stars of that type to be identified. Photometric observations dating back to 1946 provide a lengthy record of its pattern of pulsation; it undergoes periodic pulsations with a single period of 0.14088143(3) days, or 7.1 cycles per day. During each cycle, the star's magnitude varies with an amplitude of 0.15 and the radial velocity varies by 10 km s⁻¹. The peak brightness occurs 28.8 minutes following the minimum radial velocity. The outer atmosphere's effective temperature of 6,920 K is one of the lowest known for a Delta Scuti variable. Rho Puppis has an estimated age of about 2 billion years and it has 3.4 times the Sun's radius. It has a stellar classification of F5IIkF2IImF5II. This complex format indicates that ρ Puppis is an Am star, with relatively weak lines of calcium and strong lines of other metals. The spectral type indicated by the calcium k line is F5, while that indicated by heavier metal absorption lines is F2. The roman numerals indicate a

luminosity class 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 ...

bright giant A giant star is a star with substantially larger radius and luminosity than a main-sequence (or ''dwarf'') star of the same surface temperature.Giant star, entry in ''Astronomy Encyclopedia'', ed. Patrick Moore, New York: Oxford University Press ...

. Most such stars are found in binary star systems, but this appears to be an exception as no companion has been discovered. Evolved stars with Am-like peculiarities of abundance have come to be known as ρ Puppis stars. The star's metallicity is more than double that in the Sun. This star shows an excess emission of infrared radiation, suggesting that there is a circumstellar disk of dust orbiting this star. The mean temperature of the emission is 85 K, corresponding to an orbital separation from the host star of 50 AU.

References

{{DEFAULTSORT:Rho Puppis Puppis, Rho Puppis Tureis Circumstellar disks Puppis, 15 F-type bright giants Delta Scuti variables 039757 3185 067523 Durchmusterung objects