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Just like a "Butterfly": Dilly Crater... (MULTISPECTRUM; credits: Lunexit)
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This image covers the primary cavity of the distinctive rayed crater Dilly. Dilly is what is commonly referred to as a “butterfly” crater. This colloquial name refers to the asymmetry of the ejecta giving the appearance of “wings” around an elliptical cavity, and hence, the overall appearance of a butterfly. The “butterfly” appearance and elliptical cavity of Dilly (approx. 2 x 2,3 Km in diameter) are distinctive clues indicating that the crater formed from a low-angle impact (< 45°), likely from the South-West.
In addition to being a “butterfly” crater, Dilly is one of the smallest of the large rayed crater systems discovered in THEMIS nighttime infrared (temperature) images. Dilly, like its rayed counterparts such as Zunil, Gratteri, Tomini, Zumba, and the recently discovered unnamed crater seen in PSP_003611_1970, possesses distinctive rays (i.e.: spoke-like and far-traversing radial ejecta features) that are most readily viewed in THEMIS images. Crater rays are distinctive in the infrared because they are comprised of both dust and coarse, rocky materials, which are contrasted as cold (dark) and warm (bright) respectively. Because rays are ephemeral features, they are noted by scientists as a tell-tale sign of a fresh or well-preserved crater.
In the image, we can also observe that Dilly possesses a very distinctive light-toned South-West-trending streak that indicates modification by wind.
Light-toned dunes are also visible in the bottom of the crater.
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