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| | Supernova 2003gd in M74 |
 | | Presumably it had occurred about one month earlier and was probably somewhat brighter, but at that time, M74 was invisible because it was near its conjunction with the Sun. |
 | | As of June 30 and July 4, 2003, it was estimated at magnitude 14.1, on July 12 at 14.6, and on July 30 had dropped to mag 16.2. |
 | | From these data, astronomers have identified the progenitor as a red supergiant star, and calculated a mass of 8 to 10 solar masses with an extended hydrogene envelop, which probably started its life as a main sequence star of up to 12 solar masses (Smartt et.al 2004). |
| www.obspm.fr /messier/more/m074_sn2003gd.html (508 words) |
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