Mercury (planet) Mercury (planet) Mercury is the smallest and innermost planet in the Solar System. Its orbital period around the Sun of 87.97 days is the shortest of all the planets in the Solar System. It is named after the Roman deity Mercury, the messenger of the gods. Like Venus, Mercury orbits the Sun within Earth's orbit as an "inferior planet", and never exceeds 28° away from the Sun. When viewed from Earth, this proximity to the Sun means the planet can only be seen near the western or eastern horizon during the early evening or early morning. At this time it
Tempe Terra Tempe Terra Tempe Terra is a heavily cratered highland region in the northern hemisphere of the planet Mars. Located at the northeastern edge of the Tharsis volcanic province, Tempe Terra is notable for its high degree of crustal fracturing and deformation. The region also contains a large number of small shield volcanoes, lava flows, and other volcanic structures. The region is named after the albedo feature "Tempe," first used by astronomer E.M. Antoniadi in 1930 to describe a bright patch of terrain centered near 40°N, 70°W. The name comes from the Vale of Tempe, a valley located south of Mount