Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. 91 Aquarii, also known as Psi1 Aquarii, is the brightest star in a triple star system approximately 148 light-years away in the constellation of Aquarius. The system comprises three stars of which a fainter binary component is known under the name HD 219430. The primary star 91 Aqr is an orange giant star, around which an extrasolar planet is known to orbit with a mean distance from the central star slightly shorter than from Mercury to our Sun.