Pupin is a tiny lunar

Moon

The Moon is Earth's only known natural satellite,There are a number of near-Earth asteroids including 3753 Cruithne that are co-orbital with Earth: their orbits bring them close to Earth for periods of time but then alter in the long term . These are quasi-satellites and not true moons. For more...

 impact crater

Impact crater

In the broadest sense, the term impact crater can be applied to any depression, natural or manmade, resulting from the high velocity impact of a projectile with a larger body...

 located in the eastern part of the Mare Imbrium

Mare Imbrium

Mare Imbrium, Latin for "Sea of Showers" or "Sea of Rains", is a vast lunar mare filling a basin on Earth's Moon and one of the larger craters in the Solar System. Mare Imbrium was created when lava flooded the giant crater formed when a very large object hit the Moon long ago...

. It lies to the southeast of the crater Timocharis

Timocharis (crater)

Timocharis is a prominent lunar impact crater located on the Mare Imbrium. The closest crater of comparable dimensions is Lambert to the west. The smaller craters Feuillée and Beer lie to the east of Timocharis....

, and was identified as Timocharis K prior to being renamed by the IAU

International Astronomical Union

The International Astronomical Union IAU is a collection of professional astronomers, at the Ph.D. level and beyond, active in professional research and education in astronomy...

. The mare

Lunar mare

The lunar maria are large, dark, basaltic plains on Earth's Moon, formed by ancient volcanic eruptions. They were dubbed maria, Latin for "seas", by early astronomers who mistook them for actual seas. They are less reflective than the "highlands" as a result of their iron-rich compositions, and...

 near Pupin is otherwise devoid of significant impact craters, and is nearly featureless except for a faint dusting of ray

Ray system

A ray system comprises radial streaks of fine ejecta thrown out during the formation of an impact crater, looking a bit like many thin spokes coming from the hub of a wheel. The rays can extend for lengths up to several times the diameter of their originating crater, and are often accompanied by...

 material.

Despite its apparent diminutive size, Pupin is actually larger than the famous Barringer crater in Flagstaff, Arizona

Flagstaff, Arizona

Flagstaff is a city located in northern Arizona, in the southwestern United States. In 2010, the city's population was 65,870. The population of the Metropolitan Statistical Area was at 134,421 in 2010. It is the county seat of Coconino County...

.