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Peak Ring
A peak ring crater is a type of complex crater, which is different from a multi-ringed basin or central-peak crater. A central peak is not seen; instead, a roughly circular ring or plateau, possibly discontinuous, surrounds the crater's center, with the crater rim still farther out from the center. Formation The rings form by different processes, and inner rings may not be formed by the same processes as outer rings.Geology Pagewww.geologypage.com/2016/10/research-helps-explain-formation-ringed-crater-moon.html accessdate: February 5, 2017 It has long been the view that peak rings are formed in the stage subsequent to central peak formation in craters. The central peaks of craters are believed to originate from hydrodynamic flow of material lifted by inward-collapsing crater walls, while impact-shattered rock debris is briefly turned to fluid by strong vibrations that develop during crater formation. The peak-ring structure of Chicxulub crater was probably formed as inward-co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Complex Crater
Complex craters are a type of large impact crater morphology. Above a certain threshold size, which varies with planetary gravity, the collapse and modification of the transient cavity is much more extensive, and the resulting structure is called a ''complex crater''. The collapse of the transient cavity is driven by gravity, and involves both the uplift of the central region and the inward collapse of the rim. The central uplift is not the result of ''elastic rebound'' which is a process in which a material with elastic strength attempts to return to its original geometry; rather the uplift is a process in which a material with little or no strength attempts to return to a state of gravitational equilibrium. Complex craters have uplifted centers, and they have typically broad flat shallow crater floors, and terraced walls. At the largest sizes, one or more exterior or interior rings may appear, and the structure may be labeled an ''impact basin'' rather than an impact crater. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Holst (crater)
Holst is a crater on Mercury (planet), Mercury. Its name was adopted by the International Astronomical Union (IAU) on April 24, 2012. Holst is one of 110 Peak ring, peak ring basins on Mercury. To the east is another peak-ring basin, Nabokov (crater), Nabokov, of similar size. Holst lies near the center of the ancient Lennon-Picasso Basin. Holst is named for the British composer Gustav Holst, Gustav Theodore Holst. Holst composed a musical suite called ''The Planets'', including its third movement ''Mercury, the Winged Messenger''. Holst crater mosaic EN0219644465M EN0219644470M.jpg, MESSENGER NAC mosaic Holst crater MESSENGER WAC IGF to RGB.jpg, Exaggerated color image Holst dark halo crater EN0222233517M.jpg, Closeup of crater with dark halo within the peak ring References Impact craters on Mercury {{Mercury-planet-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
