An impact crater is a physical scar on a planetary body's surface (topographic depression or geological structure) that is the result of hypervelocity impact by a minor planet, such as an asteroid, comet, or meteorite. Most impact craters are...

Except for certain laboratory experiments and outdoor detonations of high explosives (including nuclear weapons), evidence of shock metamorphic conditions of extreme pressure and heat on Earth exist only within and around impact craters. Only...

Earth's surface undergoes many kinds of environmental changes that affect human life and the evolution of all living things. Some are caused by human beings, and others result from natural processes; some evolve slowly, whereas others are...

In the broadest sense, the term impact crater can be applied to any depression, natural or manmade, resulting from the high velocity impact of a projectile with larger body. In most common usage, the term is used for the approximately circular...

Impact crater may lie beneath Lake Huron With the help of magnetic sensors, scientists have detected a rimmed circular structure, 30 miles in diameter, more than a mile beneath the floor of Lake Huron. They believe the magnetic ring marks a buried...

Scientists said yesterday they have found evidence that a huge meteorite or comet plunged into the coastal waters of the Southern Hemisphere 251 million years ago, possibly triggering the most catastrophic mass extinction in Earth's history. The researchers said that geological evidence suggests...

A forest fire has led to a chance discovery of debris from the impact of a meteorite 1.85 billion years ago, more than 450 miles away at Sudbury, Ontario.Geologists had scheduled a field trip in May along the Gunflint Trail in northeastern Minnesota, but most...

NASA's aging but durable Mars rover Opportunity will make what could be a trip of no return into a deep impact crater as it tries to peer further back than ever into the Red Planet's geologic history.The descent into Victoria Crater received the go-ahead because...