MIT Technology Review crunches the numbers and figures that anyone who spends three years on Mars is going to witness an H-bomb-sized asteroid collision:
Today. William Bruckman and pals at the University of Puerto Rico at Humacao do exactly this kind of analysis but with a twist. They derive impact probabilities for Earth but also for Mars. Their conclusion is that astronauts visiting Mars for just a few years are likely to witness a significant asteroid impact.
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Their model suggests that Tunguska-type events of around 10 megatons should occur roughly once a century and smaller 1 megaton events once every 15 years. They say that both these predictions are compatible with crater counts and most other estimates.
Emboldened by this success, they apply the same model to Mars, where impact rates are likely to be higher because of its proximity to the asteroid belt. Here’s the interesting part: these guys calcaulte that Mars experiences a 1 megaton event every three years.
That’s significant because future missions to Mars may well last several years. “We expect that Mars visitors spending a few years there will have a high probability of witnessing a megaton-type meteorite impact.” they say.
That’s could have an important impact on any mission. “These impacts are likely to cause more damage on the surface than on our planet, due to the much lower atmospheric Martian density,” they conclude.