Mars Global Surveyor's Mars Orbiter Camera (MOC) Wide-Angle Images (1999-2006): 1. Data Processing

Earth-based telescopes and Mars-orbiting spacecraft have revealed Mars to be a dynamic body with periodic changes spanning hours to years, and other changes that present no discernible pattern. Understanding these surface and atmospheric variations requires observing and tracking them, and that requires global, consistent image data that spans several years. In support of that goal, the Mars Orbiter Camera Wide Angle "daily global map" images, in both red and blue, have undergone a modern processing with photometric corrections. They have been projected and blended into equirectangular and polar stereographic monochromatic and synthetic three-color mosaics in intervals of 1 day and Delta L-s = 2 degrees, 5 degrees, 10 degrees (approximately 4 days, 10 days, and 2.5 weeks, respectively). The full data set presents three dimensions of Mars-location, time, and color-while ranges or values within each dimension can be combined in different ways, presenting a highly complex interplay for exploration. In this work, the methods to generate the data are presented along with an overview of the data set. In the companion paper (Robbins, 2023a, https://doi.org/10.1029/2022JE007621), several new observations are made along with replication of known, previously described phenomena. Plain Language Summary Earth today is under constant monitoring by satellites, providing views of our dynamic world. The data collected range from visible wavelengths of light we can see with our eyes to other light such as infrared and ultraviolet. This global data set gives researchers an unprecedented way to understand our dynamic planet and, for the last roughly two decades, we have been able to do the same at Mars. The first modern craft to orbit Mars was NASA's Mars Global Surveyor, which had the Mars Orbiter Camera. A wide-angle component of that camera took red- and blue-color images globally and daily during the camera's lifetime, from 1999 through 2006. That data set has been reprocessed with more recent software, mosaicked, and grouped into several different time intervals for different types of scientific investigations. Additionally, synthetic green images were created which allow approximate true-color views of what Mars looked like during the seven Earth years that data were taken. The data reveal a dynamic world of huge cloud systems, changing surface dust patterns, seasonal changes in frost and ice cover, and vast polar cloud systems as each hemisphere slips into winter.