About 21 Vul
21 Vul is an uncommon variable star. It lies about 297.3 light-years from Earth, sits in the constellation Vul, shines at apparent magnitude 5.19 and has spectral type A7IVn.
Its spectrum reads A7IVn — 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.