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Australia

Over the Kimberley Region of northern Western Australia, satellite sensors and airplane passengers alike can see a giant arachnid sprawling over the arid landscape. This spider is not just big, it is old. This prehistoric monster crawls out of the past as if to remind us of the destructive power of the cosmos. In this false-color satellite image Spider Crater and the surrounding arid landscape appear in varying shades of crimson. Water appears blue-black, namely in the meandering river near the bottom edge of the image. Vegetation appears in shades of red. While vegetation looks sparse throughout the area, the intense red dots along the river indicate fairly lush – if intermittent – vegetation lining the riverbanks.

Strongly deformed layers of sedimentary rock give evidence of that the structure was formed by extraterrestrial trauma. Spider Crater rests in a depression some 13 by 11 km (8 by 7 mi) across. Meteorite craters often have central areas of uplift, and Spider Crater fits this pattern, with a central dome roughly 500 m (1,640 ft) in diameter. Radiating from this central dome are features unusual in impact craters in general, but important in giving this crater its nickname. Overlapping beds of tough sandstone that have weathered the elements far better than the surrounding rocks form the spider's "legs." So while Spider Crater sits in a depression and has a central uplift area characteristic of impact craters, it shows extreme differences in erosion, giving it a unique appearance. The age of Spider Crater is uncertain, but its formation has been estimated to fall between 900 and 600 million years ago. Image courtesy of NASA.