Between Mars and Jupiter lies the Asteroid Belt, where large chunks of the 170 km wide Baptistina asteroid had strayed to our side of the Solar System and hit the Moon and the Earth. One of the galactic boulders that hit our world may be the one that caused a mass extinction 65 million years ago and had wiped out the dinosaurs.

Scientists from Southwest Research Institute (SwRI) and Charles University in Prague believe that the Baptistina asteroid was hit by another asteroid measuring 60 km in diameter, causing it to spew out about 140,000 smaller pieces measuring 1 km each, and 300 more measuring 10 km each. Some of the fragments eventually broke out of orbit from the main body, with 2% of them hitting the Earth.

Scientists put the huge galactic drama within Earth's timeline, and found that the Baptistina collision may have caused the huge amount of craters whose ages go back 100 to 150 million years ago. They surmise that 20% of asteroid impact may have been caused by asteroids that broke off from the larger Baptistina family.

The event also ties up with a 85 km crater (called Tycho) on the moon, which was formed 108 million years ago. Scientists are excited at the prospects of connecting up the Baptistina collision to events on the Earth, the Moon and even on other planets. They hope to find out the implications the impact had on the geological and biological history of Earth. Maybe even how it affected human evolution.