Polar cap of Mars and its Syrtis Major

Polar cap of Mars and its Syrtis Major

Fig. 8.3 . The English amateur astronomer Warren De La Rue (1815-1889) made this drawing of Mars on 20 April 1856, using a 0.33-meter (13-inch) reflector telescope. It shows bright polar caps and a dark, triangular feature now known as Syrtis Major Planitia (Gulf of Sirte Plains). The Dutch astronomer Christiaan Huygens (1629-1695) first sketched this feature in 1659. From his observations of Syrtis Major, Huygens concluded that the rotation period of Mars is about 24 hours. This drawing is reproduced from Camille Flammarion’s (1842-1925) book La Planete Mars et ses Conditions d’Habitabilité, published in 1892.

Copyright 2010, Professor Kenneth R. Lang, Tufts University