Asteroids = Martian Birth Control Device?

For quite some time now Scientists have known that a great way to mess up life on Earth is to have an asteroid impact (just ask our dinosaur friends) but it’s interesting to think that such an event would prevent life from starting up on a planet. Well it turns out that this may be why we never got to have next door neighbors on Mars:

Asteroid blast may have thwarted life on Mars

“A giant asteroid could have destroyed Mars’s chances of evolving into an Earth-like blue planet by punching a hole in its crust so large that it damaged the red planet’s magnetic field, scientists have found. Earth’s magnetic field, generated by molten iron moving in its core, deflects radiation that would otherwise blast its atmosphere into space.

Scientists have long been puzzled why Mars lacks a similar field, but measurements from an orbiting spacecraft may have provided an answer. They have found intense magnetic anomalies affecting surface rocks all over Mars’s southern hemisphere. These appear to be remnants of a field that once embraced the whole planet.

Such anomalies are absent from the northern hemisphere, suggesting something happened to change the planet’s magnetic field in the distant past. This fits with another Mars oddity, that the rocks are much thinner in the northern hemisphere than in the south, a phenomenon known as the “crustal dichotomy”.”

Illustration swiped from marsanomalyresearch.com.