Geological Chronicle
Gardner is a circular impact crater measuring 17.62 kilometers in diameter in the northeastern quadrant of the Moon. Situated due east of Vitruvius and southwest of the larger crater Maraldi, it occupies an expanse of rugged terrain north of Mare Tranquillitatis.
The crater exhibits sharp, well-defined outer rims with minimal erosion. Its sloping inner walls descend to a central floor that spans roughly half the overall diameter, where the southern portion rises slightly before meeting the wall and a row of four rounded hills extends across the northern floor.
Directly south of the formation lies an elevated lunar feature informally called the Gardner Megadome. Originally designated Vitruvius A, the crater received official IAU naming in 1976 in honor of American physicist Irvine Clifton Gardner.