Pi1 Cygni

From Wikipedia, the free encyclopedia
Jump to navigation Jump to search

Template:Short description

Template:Other stars by Bayer designation

Pi1 Cygni
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Cygnus
Right ascension Template:RA[1]
Declination Template:DEC[1]
Apparent magnitude (V) 4.66[2]
Characteristics
Spectral type B3 IV[3]
B−V Template:Engvar −0.11[2]
Astrometry
Proper motion (μ) RA: +5.29[1] mas/yr
Dec.: −1.78[1] mas/yr
Parallax (π)1.89±0.15 mas[1]
DistanceTemplate:Rnd ± Template:Rnd ly
(Template:Rnd ± Template:Rnd pc)
Absolute magnitude (MV)−3.91[4]
Orbit[5]
Period (P)26.33 d
Eccentricity (e)0.00
Periastron epoch (T)2431306.5 ± 10.0 JD
Argument of periastron (ω)
(secondary)		0.00°
Semi-amplitude (K1)
(primary)		16.5 km/s
Details
π1 Cyg A
MassTemplate:Val[3] Template:Solar mass
Radius5.6[6] Template:Solar radius
Luminosity16,538[7] Template:Solar luminosity
TemperatureTemplate:Val[2] K
Rotational velocity (v sin i)55[8] km/s
AgeTemplate:Val[3] Myr
Metallicity [Fe/H]{{{metal_fe2}}} dex
Other designations
π1 Cyg, 80 Cygni, BD+50°3410, FK5 3733, HD 206672, HIP 107136, HR 8301, SAO 33665.[9]
Database references
SIMBADdata

Script error: No such module "Check for unknown parameters".

Pi1 Cygni (π1 Cygni, abbreviated Pi1 Cyg, π1 Cyg) is a binary star[5] in the northern constellation of Cygnus. It is visible to the naked eye, having a combined apparent visual magnitude of 4.66.[2] The distance to this system can be roughly gauged by its annual parallax shift of 1.89 mas,[1] which yields a separation of around 1,700 light years from the Sun, give or take a hundred light years.

The two components are designated Pi1 Cygni A (officially named Azelfafage Template:IPAc-en, the traditional name for the system)[10] and B.

Nomenclature

π1 Cygni (Latinised to Pi1 Cygni) is the star's Bayer designation. The designations of the two components as Pi1 Cygni A and B derive from the convention used by the Washington Multiplicity Catalog (WMC) for multiple star systems, and adopted by the International Astronomical Union (IAU).[11]

It bore the traditional name Azelfafage, derived from the Arabic ظلف الفرس Dhilf al-faras meaning "the horse track" or (probably) ذيل الدجاجة Dhail al-dajājah meaning "the tail of hen".[12] In 2016, the IAU organized a Working Group on Star Names (WGSN)[13] to catalogue and standardize proper names for stars. The WGSN approved the name Azelfafage for Pi1 Cygni on 12 September 2016 and it is now so included in the List of IAU-approved Star Names.[10] For such names relating to members of multiple star systems, and where a component letter is not explicitly listed, the WGSN says that the name should be understood to be attributed to the brightest component by visual brightness[14] - in this case Pi1 Cygni A.

In Chinese, Script error: No such module "Lang". (Script error: No such module "Lang".), meaning Flying Serpent, refers to an asterism consisting of Pi1 Cygni, Alpha Lacertae, 4 Lacertae, Pi2 Cygni, HD 206267, Epsilon Cephei, Beta Lacertae, Sigma Cassiopeiae, Rho Cassiopeiae, Tau Cassiopeiae, AR Cassiopeiae, 9 Lacertae, 3 Andromedae, 7 Andromedae, 8 Andromedae, Lambda Andromedae, Kappa Andromedae, Psi Andromedae and Iota Andromedae. Consequently, the Chinese name for Pi1 Cygni itself is Script error: No such module "Lang". (Script error: No such module "Lang"., Template:Langx)[15]

Properties

This is a single-lined spectroscopic binary with a close, circular orbit, having a period of just 26.33 days. The primary, component A, is a slightly evolved B-type subgiant star with a stellar classification of B3 IV.[3] It has an estimated 10 times the mass of the Sun and around 5.6[6] times the Sun's radius. The star radiates 16,538[7] times the solar luminosity from its outer atmosphere at an effective temperature of roughly 18,360 K.[2] It is about 25[3] million years old and is spinning with a projected rotational velocity of 55 km/s.[8]

References

Template:Reflist

Template:Stars of Cygnus

  1. ↑ a b c d e f Cite error: Invalid <ref> tag; no text was provided for refs named vanLeeuwen2007
  2. ↑ a b c d e Cite error: Invalid <ref> tag; no text was provided for refs named Soubiran2010
  3. ↑ a b c d e Cite error: Invalid <ref> tag; no text was provided for refs named Tetzlaff2011
  4. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named Anderson2012
  5. ↑ a b Cite error: Invalid <ref> tag; no text was provided for refs named Pourbaix2004
  6. ↑ a b Cite error: Invalid <ref> tag; no text was provided for refs named aaa367_521
  7. ↑ a b Cite error: Invalid <ref> tag; no text was provided for refs named Hohle2010
  8. ↑ a b Cite error: Invalid <ref> tag; no text was provided for refs named Strom2005
  9. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named SIMBAD
  10. ↑ a b Cite error: Invalid <ref> tag; no text was provided for refs named IAU-LSN
  11. ↑ Script error: No such module "citation/CS1".
  12. ↑ p. 197, Star-names and Their Meanings, Richard Hinckley Allen, New York, G. E. Stechert, 1899.
  13. ↑ Script error: No such module "citation/CS1".
  14. ↑ Script error: No such module "citation/CS1".
  15. ↑ Template:In lang AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 7 月 7 日 Template:Webarchive
Retrieved from "http://debianws.lexgopc.com/wiki143/index.php?title=Pi1_Cygni&oldid=2157006"