Space Planet Explorer is an exploration game in which the player operates a survey satellite in low Earth orbit, above a model of Earth built from NASA, ESA and USGS data with real terrain, city lights and a day/night cycle. The satellite's sonar returns only a distance, so players narrow down and identify 35 real-world points of interest, such as Mount Everest, the Mariana Trench and Angkor Wat, each with information on its geology, fauna and flora. Identifications earn research data that is spent at the International Space Station on upgrades, including a wider sonar, faster analysis, infrared for the night side of the planet and a polar orbit. Some sites can only be detected with upgraded instruments.