And what about those objects that crash into large planetary bodies - comets and asteroids? You can learn more about them in the Small Bodies, Big Impacts and Asteroids YSS topics.Д¬raters are roughly circular, excavated holes made by impact events. Resources in this topic will let you explore impacts and the results of impacts, safely. NASA scientists have created their own impacts to study this important process - on the Moon during the LCROSS mission and on comet Tempel 1 during the Deep Impact mission. Did you know that the Earth- Moon system most likely formed by the impact of the early Earth with another planet half Earth's size? The huge northern lowlands of Mars, with its very thin crust, are also likely the result of impacts - and possibly one incredibly large impact! Impacts resurfaced planets and moons, put water on the Moon and Mercury, delivered materials needed by life to Earth and elsewhere, and caused at least one mass extinction - and consequently the rise of mammals - on Earth.

In the past, larger collisions occurred, with profound effects. Currently, no known asteroids are predicted to collide with our world. Impacts by larger objects, capable of damage to people or cities, are extremely rare. Some chunks make it to Earth's surface as meteorites. Today, Earth encounters many bits of ice and rock, and most burn up in the atmosphere. This topic will explore the evidence of impacts and the stories told. Those impact scars, and the materials that make up the objects themselves, tell the story of our solar system's formation - and how planets and their moons continued to change since those early days. Collisions are at the core of solar system formation ( Birth of Worlds), and continue to be one of the most important processes throughout our solar system.

Where would you find a meteoroid