One of the more annoying battle cries of creationists, or indeed anyone who seeks to disprove the workability of the abiogenesis model, is “But 3.9 billion years ago all life would have been wiped out by an epic meteor bombardment NOT LEAVING ENOUGH TIME FOR US TO EVOLVE TO THE STATE WE ARE NOW THEREFORE GOD DID IT.”
Now, from my perspective a meteor bombardment would have had to be sustained and concentrated enough to vaporise the seas and turn the entire surface of the earth to molten slag before you could make an assertion like “All life would have died.” We’re not even talking life as we know it, just single or maybe multi-celled organisms – organisms which are numerous, resiliant and extremely quick to reproduce. If only one was left alive, life would have continued.
So it’s nice to see my untutored assumptions backed up by science. A study from the University of Colorado shows that life could easily have survived the bombardment, thus potentially increasing the age of life on earth by several hundreds of millions of years.
And if life can survive a meteor strike of such intensity, it could have survived it on other planets as well. I’m waiting with impatience for news of Mars.