"PHOENIX - A petroglyph near Phoenix may by the only record in the Western Hemisphere of a supernova that appeared in 1006 ? the brightest supernova visible from earth for more than 5,000 years."

http://news.yahoo.com/s/ap/20060607/ap_on_sc/supernova_petroglyph;_ylt=AmqvV6NXBz6MBCVxTv6AxddxieAA;_ylu=X3oDMTA4NmhocGZ1BHNlYwMxNzAw