Free course

Astronomy with an online telescope

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Described image
Figure 1 The constellation of Orion, as seen from the Teide observatory. The four bright stars at each corner and the three stars of Orion’s belt range from magnitude 0.15 (Rigel) to magnitude 2.4 (Mintaka). Many fainter stars can be seen within and around Orion, with brightnesses ranging from third to sixth magnitude.

 1.1 The magnitude scale