The Global Surveyor mission orbited Mars with the objectives of obtaining high resolution images of the surface, studying the topography and gravity, and investigating the role of water and climate on Mars. It carried instruments like the Mars Orbiter Camera and Thermal Emission Spectrometer that provided evidence of liquid water on the surface in the past and identified the volcanic rock composition of most of the surface. The mission advanced understanding of Mars through identifying a global dichotomy in topography and remnants of a magnetic field.