Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. Delta1 Lyrae is a binary star system in the constellation Lyra, approximately 1,100 light years away from Earth. The two stars complete an orbit around each other about once every 88 days. They are a spectroscopic binary, meaning the separation between the two is very small, and their orbital velocity is very high. The main star, IDS 18502+3650 A, is a bluish white star of the spectral type B2.5V, meaning it has a surface temperature of 11,000 to 25,000 kelvins. It is a dwarf star, like our Sun, but more than twice as hot in surface temperature and many times brighter.