In what year was the supernova SN 1006 observed, cited as the brightest celestial occurrence?

Answer

1006 AD

The supernova event designated SN 1006 is the event most frequently cited as the brightest celestial occurrence known to history, having been observed in the year 1006 AD.

In what year was the supernova SN 1006 observed, cited as the brightest celestial occurrence?
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