This CD contains the data from the thesis, "Constraints Upon the History of Meridiani Planum, Mars Using Sub-kilometer Crater Counting" by Sharon Pitiss. The data is divided into folders for each image used in the study. Each directory has a file with information for each image. This file is labeled "(imagenumber)info.txt". Each image has been processed and is labeled "(imagenumber).bmp". The post processed image in all of the "e" images was divided into smaller parts because of its length. When divided into segments, the top most segment was labeled with the image number followed by "a". The next segment was then labeled with the image number followed by "b" and so on. Each is a bitmap with the .bmp extension. The data for craters counted in each segment follows the same convention. Each is a text file with the .txt extension. There are five columns within the file. Column 1 = Crater Number Column 2 = Left to right location within image of crater* Column 3 = Top to bottom location within image of crater* Column 4 = Radius of crater in pixels** Column 5 = Diameter of crater in pixels** *All numbers are based on the lower left pixel of each segment being (0,0). **To get these numbers into meters, mutiply by the map scale found in the info.txt file. Each segment was added together to create a file of all of the diameters from all segments and then labeled "(imagenumber)all.txt".