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The constellation of Orion as seen from Tenerife. The main stars are labelled in yellow and lines outlining the shape of the constellation join these bright stars. At the centre of the constellation are three stars (Alnitak, Alnilam and Mintaka) in a vertical line, forming the belt of Orion. To the left is the bright red star Betelgeuse, with a bluer star Bellatrix above and to the right. These two stars form Orion's shoulders. To the right of the belt is the bright star Rigel, with the slightly fainter star Saiph below – these two stars form Orion's knees. Between the belt and these two stars a small line of three stars form the sword of Orion. A faint nebulosity can be seen around the centre of these three stars – this is the great Orion nebula.

 1.1 The magnitude scale