a) I saw a picture of the rover on the Marsian surface. What took the picture? I was under the impression that the low-budget, “microwave-oven sized” rovers parachuted down to the surface…please correct me on this.
b) Is this rover still in operation? I believe it arrived circa 1997?
IIRC, Soujourner was the rover part and Pathfinder was the stationary part. Unlike the current mars landers, Soujourner couldn’t directly send stuff back to earth. but instead had to send stuff to Pathfinder which would then relay it back to earth. I assume that Pathfinder took the picture you mention.
According to this site: http://www.robothalloffame.org/mars.html the unit stopped responding after 83 days, which was much longer than expected.
Mars’ atmosphere is too thin to allow the rovers to parachute to the surface. Instead a parachute is used for initial slowing and then the lander is cut down. Surrounded by huge air bags it falls to the surface and then bounces around to a landing.
This was used for both the current and the 1997 mission.
The Pathfinder mission was a two-part probe. There was a base station which was the actual lander, and the Sojurner rover which drove off the base station and onto the surface of Mars. The pictures of the rover were taken by cameras mounted on the base station.
The Pathfinder lander and rover were only designed to operate for a few weeks. They’re long dead.