Vishniac is the larger

crater Crater may refer to: Landforms * Impact crater, a depression caused by two celestial bodies impacting each other, such as a meteorite hitting a planet * Explosion crater, a hole formed in the ground produced by an explosion near or below the surf ...

of the

Martian Mars, the fourth planet from the Sun, has appeared as a setting in works of fiction since at least the mid-1600s. It became the most popular celestial object in fiction in the late 1800s as the Moon was evidently lifeless. At the time, the pr ...

surface feature called the Giant's Footprint. It was named after Wolf V. Vishniac, a

microbiologist A microbiologist (from Greek ) is a scientist who studies microscopic life forms and processes. This includes study of the growth, interactions and characteristics of microscopic organisms such as bacteria, algae, fungi, and some types of para ...

who died on an expedition to

Antarctica Antarctica () is Earth's southernmost and least-populated continent. Situated almost entirely south of the Antarctic Circle and surrounded by the Southern Ocean, it contains the geographic South Pole. Antarctica is the fifth-largest cont ...

. Professor Carl Sagan felt very bad for the scientist, and so found an unnamed crater at the exact longitute and latitude that he died on Mars and named it after him. The feature was originally observed by

Mariner 7 A sailor, seaman, mariner, or seafarer is a person who works aboard a watercraft as part of its crew, and may work in any one of a number of different fields that are related to the operation and maintenance of a ship. The profession of the s ...

in 1969. In 1999, the

Mars Global Surveyor ''Mars Global Surveyor'' (MGS) was an American robotic space probe developed by NASA's Jet Propulsion Laboratory and launched November 1996. MGS was a global mapping mission that examined the entire planet, from the ionosphere down through t ...

's Mars Orbiter Camera was able to provide more detailed pictures. The crater measures approximately in diameter. Its name was approved by the

International Astronomical Union The International Astronomical Union (IAU; french: link=yes, Union astronomique internationale, UAI) is a nongovernmental organisation with the objective of advancing astronomy in all aspects, including promoting astronomical research, outreac ...

in 1976.

References

Impact craters on Mars Mare Australe quadrangle {{crater-stub