SN 1990U was a type Ic supernova event in the nucleus of the galaxy NGC 7479. It was discovered July 27, 1990 by the Berkeley Automated Supernova Search after reaching magnitude 16±0.5. Initially this was classified as a Type Ib supernova, but the weakness of the neutral helium absorption lines led to a reclassification.
- Gomez, G.; Lopez, R. (July 1994), "Spectral evolution of the He-Poor supernovae 1990U in NGC 7479 and 1991A in IC 2973", The Astronomical Journal 108 (1): 195–201, doi:10.1086/117058, Bibcode: 1994AJ....108..195G
- Matheson, Thomas; Filippenko, Alexei V.; Li, Weidong; Leonard, Douglas C.; Shields, Joseph C. (March 2001), "Optical Spectroscopy of Type IB/C Supernovae", The Astronomical Journal 121 (3): 1648–1675, doi:10.1086/319390, Bibcode: 2001AJ....121.1648M
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