Axial inclination of mars

The axial inclination of Mars was identified, illustrating that like Earth, Mars has a tilted axis which causes seasonal variations similar to those on Earth. The discovery contributed to the understanding of planetary motions and their effects on climate.
 William Herschel England 1781 Axial inclination of mars

The axial inclination of Mars was identified, illustrating that like Earth, Mars has a tilted axis which causes seasonal variations similar to those on Earth. The discovery contributed to the understanding of planetary motions and their effects on climate.