Orientale impact basin on the Moon

Orientale impact basin on the Moon

Fig. 5.12 . The Orientale impact basin, shown here in a Lunar Orbiter IV image, is nearly one thousand kilometers across. It was probably created during an intense bombardment of our Moon, about 3.9 billion years ago. The collision caused ripples in the lunar crust, resulting in three concentric circular rings, standing a few kilometers high. Molten basaltic lava from the Moon’s interior subsequently flowed into the impact site, most likely about 3.2 billion years ago, creating the dark, smooth floor in the center of the basin. Much smaller, sharper, younger craters have impacted this ancient basin in more recent times. Located on the extreme western edge of the Moon, the Orientale basin is difficult to see from the Earth. (Courtesy of NASA.)

Copyright 2010, Professor Kenneth R. Lang, Tufts University