title: Chi Sagittarii
text: # Chi Sagittarii
  
  The Bayer designation Chi Sagittarii (χ Sagittarii) is shared by three star systems in the zodiac constellation of Sagittarius. The brightest of these, $χ^1$ Sagittarii and $χ^3$ Sagittarii, are separated by 0.56° on the sky. The dimmer star $χ^2$ Sagittarii is located between them, 0.10° from $χ^1,$ and is too faint to be seen with the naked eye. In 1977, the Wow! signal came from the direction of these stars.
  
  * $χ^1$ Sagittarii, 47 Sgr, HR 7362
  * $χ^2$ Sagittarii, 48 Sgr
  * $χ^3$ Sagittarii, 49 Sgr, HR 7363
  
  ## Name and etymology
  
  These three χ star, together with φ Sgr, σ Sgr, ζ Sgr and τ Sgr were Al Naʽām al Ṣādirah (النعم السادرة), the Returning Ostriches. According to the catalogue of stars in the Technical Memorandum 33-507 - A Reduced Star Catalog Containing 537 Named Stars, Al Naʽām al Ṣādirah or Namalsadirah was originally the title for four stars: φ Sgr as Namalsadirah I, τ Sgr as Namalsadirah II, $χ^1$ Sgr as Namalsadirah III and $χ^2$ Sgr as Namalsadirah IV (except σ Sgr and ζ Sgr). In Chinese, 狗 (Gǒu), meaning Dog, refers to an asterism consisting of $χ^1$ Sagittarii and 52 Sagittarii. Consequently, $χ^1$ Sagittarii itself is known as 狗二 (Gǒu èr, English: the Second Star of Dog.)
  
  