“Sagitta is a dim but distinctive constellation in the northern sky. Its name is Latin for 'arrow', not to be confused with the significantly larger constellation Sagittarius, the archer. It was included among the 48 constellations listed by the 2nd-century astronomer Ptolemy, and it remains one of the 88 modern constellations defined by the International Astronomical Union. Although it dates to antiquity, Sagitta has no star brighter than 3rd magnitude and has the third-smallest area of all constellations. Gamma Sagittae is the constellation's brightest star, with an apparent magnitude of 3.47. It is an ageing red giant star 90% as massive as the Sun that has cooled and expanded to a diameter 54 times greater than it. Delta, Epsilon, Zeta, and Theta Sagittae are each multiple stars whose components can be seen in small telescopes. ...”
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