About 18 UMa
18 UMa is an uncommon variable star. It lies about 116.9 light-years from Earth, sits in the constellation UMa, shines at apparent magnitude 4.8 and has spectral type A5V.
Its spectrum reads A5V — an A-type star: white-hot, typically about twice the Sun's mass, and the class most of the sky's famous bright stars belong to.