SX Corvi
SX Corvi is an eclipsing binary star system in the constellation Corvus, ranging from apparent magnitude 8.99 to 9.25 over 7.5 hours. The system is a contact binary also known as a W Ursae Majoris variable, where the two component stars orbit closely enough to each other for mass to have been transferred between them—in this case the secondary having transferred a large amount of mass to the primary.
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