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Corona borealis - the Northen Crown


Mythology - This crown or tiara is linked to the story of Theseus and the Minotaur. After Ariadne had helped Theseus defeat the hideous half man/half bull and find his way out of the labyrinth (using a ball of string) she married him. Unfortunately she fell out of favour on the voyage home and Theseus left her behind. Dionysus, feeling sorry for her, gave her a golden crown made by Hephaestus. The seven stars of the constellation represent the seven maidens and seven youths sacrificed to the Minotaur of Crete every year. In Christian mythology it is the crown of thorns borne by the saviour on the cross. Australian Aboriginals know this as the boomerang.
Stars - R corona borealis is a fascinating star. Most of the time it is just on the limit of visibility at 6th magnitude, but out of the blue it will fade down to magnitude 12 - 250 times fainter! The reason for this is that this star is carbon rich and ejects shells of dark soot that obscure the starlight. It is the prototype of a class of eruptive variable stars. Normally there are two naked eye stars visible within the bowl of Corona, but if you glance upwards and notice that one of the stars is missing you will know that the “sooty star” is
cloaking itself once again. Another star nearby, T corona borealis, is normally invisible to the naked eye at magnitude 10. Every once in a while it will flare up to 2nd magnitude - one of the brightest stars in the constellation. It is an example of a recurrent nova.
Visibility - Corona can be seen easily from May through to August