Unlike our Sun, which is solitary, most similar stars are binaries or multiples, meaning that two or more stars orbit each other. In fact, just 1/3 of stars like our Sun (which is a Class G star) are single, while 2/3 of similarly classed stars are multiples. However, some astrophysicists, including Charles J. Lada of the Harvard-Smithsonian Center for Astrophysics, posit that when it comes to stars and systems in our galaxy overall, only around 30% are binaries or multiples and the rest are single.