The software developer’s projects included the Magellan probe, which mapped out the surface of Venus using radar technology, and processing images from the pioneering Spirit and Opportunity rovers and their descendant missions. In addition to creating composite mosaics from multiple pictures and adding optical corrections to the rovers’ images, Deen and his colleagues have used processes such as stereo imaging to deliver relevant data about Mars’ terrain for the rovers’ “drivers.”
One of Deen’s early projects was maintaining the Video Image Communication and Retrieval, or VICAR, a software system first developed in 1966 to process images from unmanned spacecraft. “As far as we know, it’s the oldest continually updated image processing system in the world,” he said. Little of the system’s original code remains, partially because Deen rewrote much of its core library soon after he was hired. “Looking back, I’m not sure why they let such a fresh face redo their system’s infrastructure, but it worked.”
When the Voyager 2 probe sailed past Neptune in 1989, its first detailed images of the gas giant were delivered through Deen’s code. “I was quite proud at the time, and I still am. My code is ephemeral; it will go away eventually. But to have helped with such historic missions—that’s a legacy I can live with.”