Rock layers near Jordan, Mont., exposing the level (lower arrow) where the dinosaurs and many other animals and plants went extinct. The arrows point to coal beds which contain thin volcanic ash layers that were dated. Credit: [Image courtesy of Klaudia Kuiper
Asteroids Ida and Gaspra. THE IMPACT OF ASTEROIDS: Ida (left) and Gaspra (right) are just two of the billions of such rocky and metallic objects that orbit the Sun mainly between Mars and Jupiter. Shown here to the same scale, Ida is about 30km long (19 miles), and Gaspra is about 17km (11 miles). Asteroids have played a role in the evolution of life on Earth. Sometimes the orbits of asteroids bring them close to Earth and collisions ensue. Not only do scientists think some of Earth’s water…
Yucatan chicxulub crater - 182 km diameter; This shaded relief image of Mexico's Yucatan Peninsula show a subtle, but unmistakable, indication of the Chicxulub impact crater. Most scientists now agree that this impact was the cause of the Cretatious-Tertiary Extinction, the event 65 million years ago that marked the sudden extinction of the dinosaurs as well as the majority of life then on Earth.
An illustration of the Chicxulub impact crater in the Yucatán Peninsula. Located on the Yucatán Peninsula in Mexico, many scientists believe that the meteorite that left this crater caused or contributed to the extinction of the dinosaurs. Estimates of its actual diameter range from 106 to a whooping 186 miles (170 to 300 kilometers), which if proved right could mean it’s the biggest.