Every 26 months, the orbits of Earth and Mars align such that the two planets form a relatively straight line with the sun. This cosmic event is called an opposition, because the Red Planet sits on the exact opposite side of Earth from the sun.

Every 26 months, the orbits of Earth and Mars align such that the two planets form a relatively straight line with the sun. This cosmic event is called an opposition, because the Red Planet sits on the exact opposite side of Earth from the sun.