Popular name for the recurrent nova T Coronae Borealis. Two major outbursts have been observed, in 1866 and 1946, when the star reached magnitude 2.0, rapidly fading to about magnitude 9 within a month, and subsequently to its quiescent magnitude of 10.8. Other, smaller outbursts have been recorded at ultraviolet wavelengths in 1963 and 1975. The star is a spectroscopic binary, one component being an M giant, the other a massive white dwarf. The usually quoted orbital period of 227.6 days is in some doubt.