Vishniac is a largest crater of the Martian surface feature called the Giant's Footprint. It was named after Wolf V. Vishniac, a microbiologist who died on an expedition to Antarctica. Fittingly, the crater lies in the Antarctic of Mars. The feature was originally observed by Mariner 7 in 1969. In 1999, the Mars Global Surveyor's Mars Orbiter Camera was able to provide more detailed pictures.