Geological Chronicle
Briggs is an impact crater spanning 36.75 kilometers across in the western reaches of Oceanus Procellarum. Positioned east of the walled plain Struve, northeast of Eddington, and north-northwest of Seleucus, its isolated placement on the dark mare near the Moon's northwestern limb provides a clear reference point for Earth-based observers.
Formed during the Late Imbrian period, the crater deviates from a circular outline with distinct outward bulges toward the north-northeast and south. The interior ground arches upward into a floor cut by radial and concentric cracks, identifying Briggs as a floor-fractured crater shaped by subsurface uplift.
A central ridge runs north across the midpoint of the crater floor. Spectral observations indicate that this ridge matches high-calcium pyroxene, material brought up from deeper levels by the impact.
German astronomer Johann H. Schröter introduced the feature into lunar nomenclature in 1791, honoring the English mathematician Henry Briggs. The International Astronomical Union formally adopted the designation in 1935.