Free Astronomy Magazine March-April 2021

From landing to final data trans- mission, Mars Pathfinder re- turned 2.3 billion bits of in- formation, including more than 16,500 images taken by the lan- der and 550 images taken by the rover, more than 15 chemical analyses of rocks and soil, and data on winds and other mete- orological features. The results of investigations conducted by scientific instru- ments on both the lander and the rover have suggested that Mars may have been hot and humid in the distant past, with water present in a liquid state and the surface blanketed by a denser atmosphere. Sojourner was the first vehicle with wheels to roam another planet − 65 cm long, 48 cm wide, 30 cm high, 7 MARCH-APRIL 2021 MARS ROVERS T his 8-image mosaic is of Sojourner, NASA's first rover on Mars, and was acquired during the late afternoon on Sol 2, the second Martian day on the planet, as part of an “insurance panorama.” This color image was designed as “insur- ance” against camera failure upon deployment. However, the camera deployment was successful, leaving the insurance panorama to be downlinked to Earth several weeks later. Ironically enough, the insurance panorama contains some of the best quality image data because of the lossless data compression and relatively dust-free state of the camera and associ- ated lander/rover hardware on Sol 2. [NASA/JPL] S ojourner view of Mars Pathfinder base station (Sagan Memorial Station) after driv- ing off the ramps onto Mars. [NASA/JPL]