51.Mersenius

Mountainous area in-between the  west coast of Mare Humorum and the western edge of the visible side of the Moon. Along Mare Humorum, rilles and canyons.

CAVENDISH - Henry Cavendish (1731 - 1810) English chemist and physicist, discoverer of hydrogen, found the Constant of Gravitation.

Crater. (56km /35Mi ø ) (Dept: 2.550m /8,366ft) (24.64°S, 53.76°W) Overlapped by Cavendish E.

DE GASPARIS - Annibale de Gasparis (1819 - 1892) Italian astronomer. Discoverer of nine planetoids.

Crater. (32km /20Mi ø ) (Dept: 1,080m /3,543ft) (25.84°S, 50.82°W) Rim worn and eroded, interior flooded by lava, outer rim reaches a maximum altitude of about 0.8 km, formation of rilles criss-cross the floor and the surrounding surface.

DE VICO - Francesco de Vico (1805 - 1848) Italian astronomer. Discoverer of six comets, Observer of Venus.

Crater. (19Km /12Mi ø ) (19.74°S, 60.31°W) Circular, bowl-shaped formation with a small, flat bottom at the midpoint.

FONTANA - Francesco Fontana (1585 - 1656) Italian jurist and amateur astronomer. Observer of the planets.

Crater. (31Km /19Mi ø ) (Debt: 1.130m /3707ft) (16.07°S, 56.76°W) Low-rimmed circular crater.

FRERES HENRY - Paul Henry (1848 - 1905), and Prosper Henry (1849 - 1903) French astronomers, they did  the  astrophotography work for the "Carte du Ciel" sky atlas and constructed a number of big refractors and helped to develop astro-photography.

Crater. Paul. (42km /26Mi ø ) (Dept: 3.750m /12,303ft) (23.57°S, 58.99°W) Rim nearly circular.

HENRY - Joseph Henry (1797 - 1878) American scientist. Henry's work on the electromagnetic relay was the basis of the practical electrical telegraph, invented by Samuel F. B. Morse.

Crater. Prosper (41km /25Mi ø ) (Dept: 2,630m /8,628ft) (23.99°S, 56.97°W) Erosion, overlain by a pair of small craters.

MARE HUMORUM - Sea of Moister (Named by Giovanni Riccioli).

Mare (389km/247Mi ø ) (24.4°S, 38.6°W) Circular formation.

LIEBIG - Justus Freiherr von Liebig (1803 - 1873) German chemist. Inventor of a new way to coat a glass mirror with a layer of silver, so that it can be used in telescopes, a revolutionary invention.

Crater. (38km /24Mi ø ) (Dept: 2,360m /7,742ft) (24.32°S, 48.26°W) Low inner wall, Liebig A lays inside the wall.

MERSENIUS - Marin Mersenne (1588-1648) French mathematician, physicist, musical theorist. He was a defender of Galileo, assisting him in translations of some of his works. He also corresponded with Constantijn Huygens.

Crater. (84km /52Mi ø ) (Dept: 3,860m /12,664ft) (21.49°S, 49.34°W) Heavily worn, Mersenius N lies across the southwestern rim, interior flooded by lava.

PALMIERI - Luigi Palmieri (1807 - 1896) Italian mathematician and geophysicist who studied of the eruptions of Mount Vesuvius.

Crater. (40km /25Mi ø ) (Dept: 1,200m /3,937ft) (28.62°S, 47.77°W) Eroded outer rim, gaps along the northern rim, flooded by lava, floor marked by a system of rilles named the Rimae Palmieri that continue to the north and southeast beyond the crater for about 150 kilometers.

51.