The eighth brightest star in the constellation Aquila and one of the sky's most prominent Cepheid variables; its variability was discovered in 1784 by Edward Pigott. Eta Aql lies 8° south of Altair and near one of Aquila the Eagle's talons. Eta also represents the head of the now-defunct constellation Antinous, who was honored in the sky by the Roman emperor Hadrian and depicted as being carried by Aquila. Eta, like other Type I Cepheids is a luminous yellow-white supergiant. It changes brightness by 0.8 magnitude and back again with precise period of 7d 4h 14m 22s. As it dims, it dips to spectral class G and from a maximum temperature of 6,200 K to 5,300 K.
Related categories NOTABLE STARS
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