Ainalrami

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Star
Ainalrami (Ain al Rami) (ν¹ Sagittarii)
Ain al Rami in the constellation Sagittarius
AladinLite
Observation
dates equinox :  J2000.0 , epoch : J2000.0
Constellation Sagittarius
Right ascension +18 h 54 m 10.18 s
declination −2244 ° 41.4247 ′
Apparent brightness +4.86 mag
Typing
B − V color index +1.43 
U − B color index +1.34 
Spectral class G2 / K1 Ib / II + B9.2p
Astrometry
parallax (2.90 ± 0.30)  mas
distance 1,100  ly
340  pc
Visual absolute brightness M vis −3.91 mag
Proper movement 
Rec. Share: 2.59  mas / a
Dec. portion: 8.41  mas / a
Physical Properties
Other names
and catalog entries
Bayer name ν¹ Sagittarii
Flamsteed name 32 Sgr
Bonn survey BD −22 ° 4907
Bright Star Catalog HR 7116 [1]
Henry Draper Catalog HD 174974 [2]
Hipparcos catalog HIP 92761 [3]
SAO catalog SAO 187426 [4]

Ainalrami or Ain al Rami ( Ny¹ Sagittarii , ν¹ Sagittarii ) is a triple system at an approximate distance of 1,100 light years in the constellation Sagittarius (Latin: Sagittarius). Its three components are named Ny¹ Sagittarii A , B and C after the Bayer name . A and B in turn form a spectroscopic double star .

nomenclature

Ail al Rami (IAU spelling Ailalrami ) is a traditional name that is derived from the Arabic عين الرامي c ain ar-rāmī , which means eye of the archer .

ν¹ Sagittarii ( Latinized Ny¹ Sagittarii ) is the Bayer name of the system. Ny¹ and Ny² Sagittarii (collectively referred to as Ny Sagittarii ) bear the traditional name . In 2016, the International Astronomical Union organized a working group WGSN (Working Group on Star Names) to catalog and standardize star names . The WGSN confirmed the name Ain al Rami on September 5, 2016 for the component Ny¹ Sagittarii A and included it in the list of IAU-confirmed star names.

Ny¹ and Ny² Sagittarii are called Al Ud Aliyy , the ostrich nest, together with Tau Sagittarii , Psi Sagittarii , Omega Sagittarii , 60 Sagittarii and Zeta Sagittarii .

properties

Ny¹ Sagittarii A is a bright giant star of the spectral type K1 with an apparent magnitude of +4.86 mag . It is weakly variable with a frequency of 0.43398 cycles per day and an amplitude of 0.0078 mag. In 1982 a hotter companion was found, Ny¹ Sagittarii B, a rapidly rotating star of the spectral type B9. They circle each other with a period of about 370 days. Another, more distant companion of magnitude +11.2 mag, component C, orbits the main star at an angular distance of 2.5 arc seconds .

Individual evidence

  1. ^ A b F. van Leeuwen: Validation of the new Hipparcos reduction , Astronomy and Astrophysics, 2007, Volume 474, Issue 2, Pages 653-664, arXiv 0708.1752
  2. ↑ a b c T. E. Lutz, JH Lutz: Spectral classification and UBV photometry of bright visual double stars , Astronomical Journal, June 1977, Volume 82, Pages 431-434, doi 10.1086 / 112066
  3. ^ Sidney B. Parsons, Thomas B. Ake, Ultraviolet and Optical Studies of Binaries with Luminous Cool Primaries and Hot Companions. V. The Entire IUE Sample , The Astrophysical Journal Supplement Series 1998, Volume 119, from page 83, doi 10.1086 / 313152
  4. ^ D. Cardini: Mg II chromospheric radiative loss rates in cool active and quiet stars , Astronomy and Astrophysics, January 2005, Volume 430, Pages 303-311, arXiv astro-ph / 0409683
  5. ^ A b c d P. P. Eggleton, AA Tokovinin: A catalog of multiplicity among bright stellar systems , Monthly Notices of the Royal Astronomical Society, September 2008, Volume 389, Issue 2, Pages 869-879, arXiv 0806.2878
  6. ↑ a b Naming Stars . IAU.org. Retrieved December 16, 2017.
  7. ↑ a b Washington Double Star Catalog ( Memento of the original from February 14, 2011 in the Internet Archive ) Info: The archive link was automatically inserted and not yet checked. Please check the original and archive link according to the instructions and then remove this notice. @1@ 2Template: Webachiv / IABot / ad.usno.navy.mil
  8. ↑ a b R. H. Allen: Star Names: Their Lore and Meaning (Reprint ed.) . New York: Dover Publications Inc. (1963), page 355. ISBN 0-486-21079-0
  9. ↑ Chris Koen, Laurent Eyer: New periodic variables from the Hipparcos epoch photometry , Monthly Notices of the Royal Astronomical Society, 2002, Volume 331, Page 45, arXiv astro-ph / 0112194
  10. ^ Y. Kondo, GE McCluskey, CC Wu: The early-type component in ν¹ Sagittarii , Astronomical Society of the Pacific, August 1982, Volume 94, pages 647-649, doi 10.1086 / 131037