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
Aonia Terra Aonia Terra Aonia Terra is a region in the southern hemisphere of the planet Mars. It is named after a classical albedo feature, the "Bay of the Muses" and its name was approved in 1979, by the International Astronomical Union (IAU) Working Group for Planetary System Nomenclature. It is centered at and covers 3900 km at its broadest extent. It covers latitudes 30 to 81 South and longitudes 60 to 163 W. Aonia Terra is an upland area notable for massive cratering including the large Lowell Crater, parts of the region features small craters, in the plain areas, Thaumasia Fossae