Virrat (crater)

Virrat is a Martian impact crater, approximately 54 kilometres in diameter. It is located at 31.1°S, 103°W, southwest of the crater Dinorwic and northeast of Clantas Fossae. Several Virrat crater radii to the north are the craters Koga and Nhill. It is named after a town in Finland, and its name was approved by the International Astronomical Union in 1991. According to a surface age map of Mars based on US Geological Survey data, the area around Virrat is from the Noachian epoch, which places the area's age at 3.8 to 3.5 billion years ago. At the highest point on its rim, it is about 6,400 metres above zero altitude, and it is about 5,100 metres at the crater bottom, giving it a depth of 1.3 kilometres.