U Geminorum [SEP] constellation
U Geminorum
U Geminorum ("U Gem"), in the constellation Gemini, is an archetypal example of a dwarf nova. The binary star system consists of a white dwarf closely orbiting a red dwarf. Every few months it undergoes an outburst that greatly increases its brightness. The dwarf nova class of variable stars are often referred to as U Geminorum variables after this star.
Discovery.
U Geminorum was discovered by J.R. Hind in 1855 who initially thought it was a nova; it quickly faded below his telescope
Nova Persei 2018
Nova Persei 2018 is a bright nova in the constellation Perseus discovered on April 29, 2018. It was previously known as a dwarf nova with variable star designation V392 Persei.
Dwarf nova.
A "U Geminorum-type variable star" or "dwarf nova" is a type of cataclysmic variable star consisting of a close binary star system in which one of the components is a white dwarf that accretes matter from a cool main sequence or subgiant companion. V392 Persei was discovered in 1970 and received