Mons Huygens Mons Huygens Mons Huygens is the Moon's tallest mountain (but not its highest point). It is about high and is located in the Montes Apenninus. The Montes Apenninus were formed by the impact that created Mare Imbrium. Adjacent is Mons Ampère to the west. Further west is the crater Huxley. The mountain was named after the Dutch astronomer, mathematician and physician Christiaan Huygens, it was officially named by the IAU in 1961. Mons Huygens is high, about the same height as Aeolis Mons located on Mars in the middle of Gale crater, and taller than Mons Hadley located on the
Tharsis Montes is about across and stands above the ocean floor. The Tharsis Montes volcanoes lie near the equator, along the crest of a vast volcanic plateau called the Tharsis region or Tharsis bulge. The Tharsis region is thousands of kilometers across and averages nearly above the mean elevation of the planet. Olympus Mons, the tallest known mountain in the Solar System, is located about northwest of the Tharsis Montes, at the edge of the Tharsis region. The Tharsis Montes were discovered by the Mariner 9 spacecraft in 1971. They were among the few surface features visible as the spacecraft entered orbit