Delaunay is a lunar crater. The craters La Caille to the southwest and Faye to the northeast border on the outer rim of Delaunay. Further to the northwest is the prominent Arzachel.
This is an irregular crater formation that has an interior ridge running from the northeast side that divides the crater nearly in half, and gives it a heart-shaped appearance. This ridge grows increasingly slender as it approaches the southwest rim, until it terminates at sharp point, giving it the appearance of a curved fang. The outer rim of this crater is equally irregular, and the uneven inner wall varies significantly in width. The southern rim in particular has been heavily damaged by impacts, including La Caille E which intrudes into the interior.
Delaunay is a French surname. Notable people with the surname include: