Catch a failing star: the tense wait for a supernova

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By Robin McKie, The Guardian. 

Excerpt: ...When a supernova erupts, it sprays the cosmos with heavy elements – so observing one nearby would provide precious information about the creation of matter in our galaxy. ...Scientists estimate that on average about 20 supernovae occur in a galaxy such as ours every thousand years. Yet only five have been observed in the last millennium. East Asian and Arabic records indicate there were supernovae in 1006, 1054 and 1181, while European documents recall ones that occurred in 1572 and 1604. ...if supernovae are so brilliant, why have we only detected five in the past 1,000 years? Why have we not seen a number that is nearer the 20 suggested by observations of other galaxies? The answer is straightforward, says Sullivan. “Our galaxy is like a flat plate and our solar system is about two-thirds of the way towards its edge. A supernova that occurs on the other side of the plate will simply be obscured by all the dust and stars that lie at the centre of the galaxy.”…

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