When the Moon was volcanic, magma seeped to the surface, filled the basins and eventually hardened, resulting in the relatively smooth flat areas seen today. Scientists can tell this happened recently, in geological terms, because the maria have fewer impact craters than the highland areas. Its main objective is to test out new electric propulsion for future space missions.
Trending Latest Video Free. LXI, pp. Enable full ADS. Similar Papers. Volume Content. Export Citation. An area with high density of craters on the lunar surface.
This view of Mare Imbrium also shows numerous secondary craters and evidence of material ejected from the large crater Copernicus on the upper horizon. Copernicus is an impact crater almost kilometers in diameter that was formed long after the lava in Imbrium had already been deposited. Today, we know that the maria consist mostly of dark-colored basalt volcanic lava laid down in volcanic eruptions billions of years ago. Eventually, these lava flows partly filled the huge depressions called impact basins , which had been produced by collisions of large chunks of material with the Moon relatively early in its history.
The basalt on the Moon Figure 4a is very similar in composition to the crust under the oceans of Earth or to the lavas erupted by many terrestrial volcanoes. The youngest of the lunar impact basins is Mare Orientale, shown in Figure 4b. Figure 4: Rock from a Lunar Mare and Mare Orientale a In this sample of basalt from the mare surface, you can see the holes left by gas bubbles, which are characteristic of rock formed from lava.
All lunar rocks are chemically distinct from terrestrial rocks, a fact that has allowed scientists to identify a few lunar samples among the thousands of meteorites that reach Earth. Its outer ring is about kilometers in diameter, roughly the distance between New York City and Detroit, Michigan. It is located on the edge of the Moon as seen from Earth. What we do know is that the major mare volcanism, which involved the release of lava from hundreds of kilometers below the surface, ended about 3.
The primary forces altering the surface come from the outside, not the interior. The surface is fine and powdery. I can pick it up loosely with my toe. But I can see the footprints of my boots and the treads in the fine sandy particles.
The surface of the Moon is buried under a fine-grained soil of tiny, shattered rock fragments. The upper layers of the surface are porous, consisting of loosely packed dust into which their boots sank several centimeters Figure 5. Figure 5.
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