Quote:
Originally Posted by PeterM
NGC908 has had 2 recorded Supernova 1994ai Williams & Martin (Perth Automated Supernova Search) @mag17 & SN2006ce @mag17.5 Monard ( South Africa).
It's about 65 MLY years distant.
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Hi Pete,
Two supernovae in under 20 years sounds like a good rate!
It is worth keeping an eye on this galaxy for SNe....
A few "back of the envelope calculations" show that NGC 908 could be a good candidate for multiple observable supernovae in the future:
(1) If its estimated luminosity in the Hyperleda database is correct (Absolute blue magnitude of -21.4) then NGC 908 is noticeably more luminous than the Milky Way.
(2) This galaxy is likely to be very comparable to the first-ranked spiral galaxies in the Virgo Cluster of Galaxies, such as M61 and M100, for instance, the total star formation rate of NGC 908 (derived from its far-infrared luminosity) is similar to that of one of these large and luminous spirals in the Virgo Cluster.
(3) This is a physically large galaxy, bigger than the Milky Way Galaxy, and it has Very Strong spiral arm structure.
(4) Its U-B color index shows that there is plenty of ultraviolet light, coming no doubt from a large population of OB stars.
These four facts indicate that NGC 908 has a significant rate of current star formation, and therefore a high rate of core-collapse supernovae. It is a
nearby and
physically large Sc spiral galaxy with
strong spiral structure, very much like some of the other galaxies that have had several observed SNe.
I am wondering about the faintness of the observed NGC 908 supernovae, as per your post.....were they underluminous type II events? Or was there heavy extinction within this galaxy that made them fainter than they should have been?
best regards, Robert