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Solutions to the Red Supergiant Problem can be either observational or physical, and to date, both types have been proposed. Recent data and improved computer modeling have both helped make the later stages of red supergiant evolution clearer, leading to possible solutions to the problem. Walmswell & Eldridge (2012) suggested an observational solution, ...


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Firstly, the figure you quote is disputed and must have very substantial uncertainties. The same wikipedia article also cites 3 per century. Second, and more importantly, you have not accounted for dust obscuration. Most type II supernovae will occur in massive stars close to the Galactic plane and will be afflicted by huge amounts of extinction. If we ...


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So from this I can only come to the conclusion that supernovae did in fact happen in the Milky Way in the last two centuries, but that we didn't see any of them. But now I'm confused. I read about supernovae that have happened in galaxies billions of light-years from here that lit up as the brightest source of light in the sky for days. Surely ...


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Some supernovæ are more super than others, but that is not the reason that we have not observed one in 300 years. There have been 5 or 6 naked eye supernovae in the last 1000 years, There have certainly been others (such as Cassiopeia A and Supernova remnant G1.9+0.3 But they have have been hidden by the dense dust and gas in the plane of the galaxy. Some ...


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The coordinate system in this image is RA and Dec. It is a coordinate system which uses the Earth's equator (projected onto the sky) as its midline. The inverted U is the Milky Way. The Milky Way is full of dust and gas, and blocks our view of galaxies (and supernovae) behind it. There is enough dust in the plane of the galaxy to block our view in that ...


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I saw a similar "ufo" several decades ago, before there were Iridium satellites. Possibly it was another type of satellite with large reflective panels. Thinking it over, I later decided that if an airplane reflected the sunlight directly toward me at one moment of a turn, it might make a similar flash.


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Is it incorrect to call the explosion “supernova”? Yes and no. Better said, the explosion is the very first part of a supernova. While the explosion lasts for but a few seconds to a few hundreds of seconds, a supernova can last for hundreds of days. What we see visibly as a supernova are the after effects of that explosion. The explosion can create lots ...



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