The web site and database were created and maintained by one engineer, Bob Kanefsky, and advised by two scientists, Nadine Barlow and Virginia Gulick.
The original phase ran from November 2000 to September 2001, identifying and classifying the age of craters on Mars images from Viking Orbiter that had already been analyzed by NASA.
The goal was to answer two meta-science questions: In February 2001 clickworkers started processing new images from Mars Global Surveyor, surveying small craters never before cataloged.
The second task took a different approach and displayed wider field views from the older MOC camera on Mars Global Surveyor.
The landforms on these wider views were then marked, and interesting features could be tagged for possible future hi-res imaging with HiRISE.