SN 1998S was a
type IIn supernova
A Type II supernova (plural: ''supernovae'' or ''supernovas'') results from the rapid collapse and violent explosion of a massive star. A star must have at least 8 times, but no more than 40 to 50 times, the mass of the Sun () to undergo th ...
that was detected in
NGC 3877
NGC 3877 is a type Sc spiral galaxy that was discovered by William Herschel on February 5, 1788. It is located below the magnitude 3.7 star Chi Ursae Majoris in Ursa Major.
Supernova
The Type IIn supernova SN 1998S is the only supernova th ...
in March 1998. At the time of discovery, SN 1998S was the brightest type IIn event observed, although later outshone by
SN 2010jl.
It was discovered on 1998 March 2.68
UT in
NGC 3877
NGC 3877 is a type Sc spiral galaxy that was discovered by William Herschel on February 5, 1788. It is located below the magnitude 3.7 star Chi Ursae Majoris in Ursa Major.
Supernova
The Type IIn supernova SN 1998S is the only supernova th ...
by Z. Wan at a broadband (unfiltered) optical magnitude of +15.2.
Its spectrum showed prominent H and He emission lines with narrow peaks and broad wings, superimposed on a blue continuum. These narrow lines indicate the presence of a dense circumstellar medium (CSM) in the vicinity of the supernova. The high luminosity of SN1998S is due to the interaction of fast material (ejecta) with previously-expelled slowly-expanding material (CSM), which can more effectively convert kinetic energy of ejecta into radiation energy.
References
External links
Light curves and spectra on th
Open Supernova CatalogSimbad* http://www.astro.utoronto.ca/DDO/research/DDOSNe.html
Supernova remnants
Supernovae
Ursa Major
Astronomical objects discovered in 1998
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