Columbus Crater is a crater in the Memnonia quadrangle of Mars, located at 29.8° south latitude and 166.1° west longitude. It is 119 km in diameter and was named after Christopher Columbus, Italian explorer (1451–1506). The discovery of sulfates and clay minerals in sediments within Columbus Crater are strong evidence that a lake once existed in the crater. Research with an orbiting near-infrared spectrometer, which reveals the types of minerals present based on the wavelengths of light they absorb, found evidence of layers of both clay and sulfates in Columbus crater. This is exactly what would appear if a large lake had slowly evaporated. Moreover, because some layers contained gypsum, a sulfate which forms in relatively fresh water, life could have formed in the crater.