NASA Satellite Reveals 'Spider Crater' in Australian Desert
A Landsat 9 image captures a uniquely shaped impact structure, prompting geological inquiry.
NASA has released a striking satellite image of a mysterious geological formation in Australia's Kimberley region, dubbed 'Spider Crater' for its unusual, leg-like appearance.
The image, captured by the Landsat 9 satellite, showcases a large oval-shaped structure, measuring eight by seven miles. Its central portion, resembling a spider's body, spans 2.5 miles across.
While the formation might appear otherworldly, NASA explains it is the result of a meteorite impact that occurred between 600 million and 900 million years ago, followed by hundreds of millions of years of erosion. Sparse green vegetation contrasts with the red desert rocks, with a thin stream meandering through the crater, supporting thicker plant life along its banks.
Geologists were initially puzzled by Spider Crater's shape after its discovery in the 1950s. However, evidence uncovered in the 1970s pointed to an extraterrestrial origin. Researchers identified grooved, cone-shaped fractures in the rock, known as shatter cones, which are characteristic signs of intense shock waves from an impact. Distorted layers of sedimentary rock further supported the theory, indicating the immense forces involved when an object from space struck the Earth.
Laboratory analysis of shocked quartz and zircon crystals within the sandstone has provided additional clues, potentially helping scientists reconstruct the angle of the meteorite's impact. However, the precise timing of the event remains a mystery.
The remote location and rugged terrain of Spider Crater make it difficult to access, with its distinctive pattern best appreciated from aerial or satellite views. Some earlier theories suggested a volcanic origin, but the geological evidence of shatter cones and shocked minerals strongly supports an impact event.
Australia is also home to what is considered the world's oldest impact crater, the North Pole Dome in Western Australia's Pilbara region. In July, researchers confirmed through advanced mineral dating techniques that this crater was formed by a space rock impact 3.02 billion years ago. Despite billions of years of erosion, this ancient impact left a lasting geological legacy, potentially influencing early Earth environments and the conditions for microbial life.