P2K: What were some of the most important suggestions to come out of design reviews?

Pete Theisinger: Well, the original concept for this mission... At the time around May of 2000, when the Mars Program was being re-examined and restructured (ed: after the failures of the 2 Mars 98 missions), there was a bunch of design options, concepts for a variety of options that were brought forward. This mission was one of those, brought forward at that time.

And the concept was to take the ATHENA architecture-ATHENA was a rover that had been a Discovery proposal, and then was planned to go on the Mars Sample Return mission in somewhat larger variety-and to take that mission concept and to add to it some key infrastructure, like telecommunications equipment that would be required for the rover to go over the horizon from the Lander, and to put that rover inside the Pathfinder landing system, and just fit it inside the Pathfinder landing system, and it will go to Mars. And that was the concept that was adopted to go forward, and that's what we worked on in the summer of 2001.

When we did that we found out that we couldn't quite get it all in the Pathfinder landing system, and so we had to make some size adjustment to the Pathfinder landing system, and it was relatively minor-it was an inch or two, in terms of its dimensions-to make sure we had the right volume and those kinds of things. But it was a significant hiccup in terms of trying to get the design complete and to make sure we had adequate margins without being too conservative, and that was the major re-design. What that meant was that several things that we were going to build-to-print, pick up from Pathfinder and send out to fabrication shops, and have them put together, had to go now through a redesign cycle, drawings that we weren't going to draw had to be drawn. All that stuff had to be done, and that's been a major element of the work that the Project's been engaged in since January (2001.)