Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. Epsilon Aquilae is a triple star system in the constellation Aquila. Epsilon Aquilae is more precisely called Deneb el Okab Borealis, because is situated to the north of Zeta Aquilae, which can therefore be called Deneb el Okab Australis.The primary component, Aquilae A, is an orange K-type giant with an apparent magnitude of +4.02. It has two 10th-magnitude companions separated from the primary by 131.1 and 148.6 arcseconds, but perhaps they are only optical binaries. Epsilon Aquilae is approximately 154 light years from Earth. It is a so-called barium star; therefore its atmosphere is extremely enriched with barium and other heavy elements.