asteroid2These days we freak out whenever some dinky bollide explodes in the sky over Russia. But scientists have now reconstructed the effects of an enormous 3.26-billion-year-old asteroid impact on Earth that boiled the oceans, turned the sky red hot, and generated a half-hour-long earthquake that shook the planet. Though we have heard about ancient impacts such as the dinosaur-killing asteroid that hit our planet 65 million years ago, the image above really gives a sense of perspective for these events. To have looked up in the sky and seen a space rock that dwarfed any mountain on Earth would have been chilling. The gigantic object was about 30 miles wide, roughly the width of Rhode Island. It struck an area of what is now South Africa, generating a crater that would have stretched halfway across that country. The energy it released boiled the top layer of the ocean and sent tsunamis hundreds of feet high through the remaining waters. Researchers know all this from studying fractures in a rock layer in South Africa known as the Barberton greenstone belt, one of the oldest rock formations on Earth. These fissures were created when the asteroid slammed into the ground at more than 42,000 miles per hour. More