Planetary Properties (2) ...

Increased understanding of Mars had to await the results of space probes. These began with Mariner 4, 6, 7, and 9 in the period 1965-1971, the Viking 1 and 2 probes in 1976, and the 1997 Mars Pathfinder lander and Mars Global Surveyor orbiter missions. The following image is from Pathfinder.

Technically Speaking: Getting to Mars with Global Surveyor

Here is an animation of the Global Surveyor trajectory to Mars, and the aerobraking maneuver that it used to convert its initial highly elliptical orbit into a circular one more suitable for mapping the planet.


It shows the Mars rover Sojourner examining a rock that was named "Yogi". The marked two-tone appearance of the rock is thought to be the result of wind-blown dust accumulating on the side of the prevailing wind (the left side) or perhaps because it was broken out of a larger boulder.