Gassendi is an impact crater located on the near side of the Moon, on the northern edge of Mare Humorum. The hills near the floor of the center is the central peak of the crater, with a height of about 1.2 km. The crater on the northern edge of the wall is called 'Gassendi A'.

Gassendi is a scientifically interesting spot because it offers the possibility of probes lunar rocks in the mountains old sample (the central peak of the crater), and provide ages, both the Humorum impact basin itself as the Gassendi crater. However, because the land outside the crater is quite hard, the crew of Apollo 17 did not land in this region, it would be very difficult to reach the central peaks of Gassendi for sampling.

The age of Gassendi crater is estimated to be about 3.6 billion years (with a plus or minus 700 million years error).

When observed through spectroscopic analysis, the Gassendi crater has a "behavior" very different from any other lunar crater (Mikhail 1979). High resolution studies performed in the light of near infrared (Chevrel and Pinet 1990, 1992) indicated the presence of extrusive volcanic material (which is volcanic material flowing off the surface and then crystallizing) limited to the southern part of the floor Gassendi which is adjacent to Humorum mare.

The interpretation of these data suggest that the central part of the crater, including the peak complex may have a more nature 'mafic' (that is a composition of rocks solidification from the melt that is rich in iron and magnesium silicates, such as olivine and pyroxene), pyroxene with a component higher than in neighboring plateaus.

Interpretation of the data also suggested that a large extrusive volcanism may have occurred in the eastern portion of the floor, as also indicated by the significant presence of pyroxene, which corresponds to visible volcanic features. The western part of the crater floor, away from the geometric continuation of the western edge of Mare Humorum, is composed of highlands-rich material.

The difference between the western and eastern side of Gassendi with intensely fractured ground may be strongly linked to early thermal history of Mare Humorum.

The crater of 110 Km is named after Pierre Gassendi (1592-1655), French philosopher, scientist and mathematician. In 1631, Gassendi became the first person to observe the transit of a planet across the Sun, seeing the transit of Mercury which Kepler had predicted.

ESA - European Space Agency

Adaptation: Avani Soares