Schnetzler is best known for analyzing moon rocks brought back by the Apollo program and for studying the Earth's environment using the Landsat and the Earth Observing System.
This sounding was one of only a few that were ever incorporated into US nautical charts, having been derived not from sonar or lead line data, but from radiometric data from the Landsat Multispectral Scanner (MSS) imagery.
In 1972, The Landsat Program, a series of satellite missions jointly managed by NASA and the U.S. Geological Survey, began supplying satellite images that can be geologically analyzed.
This operation was successful, and on September 5, 2003, the ETM+ instrument was turned on and acquired data that was sent to the Landsat ground system at EROS outside of Sioux Falls, South Dakota.
In August 2004, a memorandum from the White House Office of Science and Technology Policy (OSTP) directed Federal agencies to place Landsat-type sensors on the National Polar-orbiting Operational Environmental Satellite System (NPOESS) platform.