Salgorax

Salgorax was an M class red star in the Salgorax-Neptor binary star system, the twin star of Neptor.

On rare occasions, one of the binaries produces a dramatic solar flare in its corona, inducing the other to flare. The flares synchronize to form a brilliant, fiery arch that emits strong radiation bursts. This spectacle can be seen safely from the surface of the planet Santar.

History
In 2265, Neptor flared, triggering the arch phenomenon for the first time in a century. At that moment, the Federation starship USS Enterprise (NCC-1701) was in orbit of Santar and beaming James T. Kirk and Spock to the surface. Radiation misdirected the transporter beam to Muton in the adjacent star system.