The Cosmic Catastrophes Chart / Poster is 22.5x29 inches, (56x73cm). This chart of the Cosmic Catastrophes includes the greatest mass extinction of all time that occurred about 240 million years ago eliminating about 96% of all species! This vivid chart examines mass extinctions froms Earth's past and explores the possibility of future extinctions. Learn about life threatening events such as cosmic impacts, ozone destruction, exploding stars and much more! This chart deals with the startling impact of cosmic disruptions on our Earths eco-structure. This attractive and educational chart is a wonderful reference for the classroom, home or office.