![]() Since the late 1950's, studies of this crater have presented an increasingly clearer view of this impact and its effects and have provided an improved view of impact cratering in general. Today, Meteor Crater continues to serve as an important research site for the international science community, as well as an educational site for over 300,000 visitors per year. Geological Survey to use the crater extensively in the 1960-70's as a prime training site for the Apollo astronauts. In 1960, Shoemaker presented information that conclusively demonstrated that Meteor Crater was formed by hypervelocity impact. Recognition of the value of the crater was initiated in the early 1900's by Daniel Moreau Barringer, whose 27 years of exploration championed its impact origin. Excellent exposures and preservation of this large crater and its ejecta blanket have made it a critical data set in both terrestrial and planetary cratering research. Meteor Crater in northern Arizona represents the most abundant type of impact feature in our Solar System, i.e., the simple bowl-shaped crater. ![]() We suggest that unit S14 has a thickness of at least a few hundreds of meters up to about 400 m.Meteor Crater ( Barringer Meteorite Crater), Arizona: Summary of Impact Conditions Furthermore, the modeling results allow advancing some hypotheses on the geological evolution of the Mare Serenitatis region where Linné crater is located (unit S14). Observations suggest that these large-scale material properties likely include some important smaller scale variations, disclosed as subtle morphological steps in the crater walls. The modeling analysis allows us to derive important clues on the impactor size (under the assumption of a vertical impact and collision velocity equal to the mean value), and on the approximate, large-scale preimpact target properties. We have also found that the truncated-cone morphology of Linné might originate from an incomplete collapse of the crater wall, as the breccia lens remains clustered along the crater walls, while the high-albedo deposit on the crater floor can be interpreted as a very shallow lens of fallout breccia. The two-layer model shows that the interface between the two layers would be exposed at the observed depth of 100 m when an intermediate value ( 200 m) for the upper fractured layer is set. In particular, a cohesion of 10 kPa marks the threshold between conical- and parabolic-shaped craters. The one-layer model shows that the largest variations in the crater shape take place when either the cohesion or the friction coefficient is varied. For the local surface, we consider either one or two layers, in order to test the influence of material properties or composite rheologies on the final crater morphology. In the initial setup, we adopt a basaltic projectile impacting the Moon with a speed of 18 km s -1. Using the iSALE shock physics code, we numerically model the formation of Linné crater to derive hints on the possible impact conditions and target physical properties. The kink at -100 m might be related to the interface between two different rheological layers. ![]() We perform morphometric measurements, including slope and profile curvature, on the Digital Terrain Model of Linné, finding the possible presence of three subtle topographic steps, at the elevation of +20, -100, and -200 m relative to the target surface. Recent high-resolution data acquired by the Lunar Reconnaissance Orbiter Camera revealed that the shape of this impact structure is best described by an inverted truncated-cone. ![]() Linné is a simple crater, with a diameter of 2.23 km and a depth of 0.52 km, located in northwestern Mare Serenitatis.
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