Geological Chronicle
Descartes is a heavily worn impact crater in the rugged south-central highlands of the Moon, spanning 47.73 kilometers in diameter. Its outer rim survives only in stretches and is completely missing to the north, while the crater Descartes A lies across the southwest rim. Within the interior floor, several curved ridges run concentric with surviving outer walls to the northwest and southeast, forming the remains of an inner ring.
A section of the outer rim exhibits higher albedo than the surrounding terrain, coinciding with the strongest magnetic anomaly on the nearside as measured at low altitude by Lunar Prospector. This localized magnetic field may deflect solar wind particles, protecting the underlying surface from darkening caused by space weathering, a mechanism similar to the bright swirls seen at Reiner Gamma, Mare Marginis, and Mare Ingenii.
About 50 kilometers north of Descartes lies the landing site of Apollo 16, set amid the uneven terrain known as the Descartes Highlands or Descartes Mountains. The feature takes its name from French philosopher, mathematician, and physicist René Descartes, introduced into lunar nomenclature by Johann H. von Mädler and formally adopted by the IAU in 1935.