Life on Earth has thrived without interruption for 3.5 billion years. This despite the asteroids and comets that have regularly threatened it (see commentary). But the planet was not always so fortunate. For the first billion years after its forming, Earth underwent periodic bombardments that were severe enough to destroy early life (if it existed then). And its not just space objects that have put our home at risk. Scientists have determined that a massive solar flare struck in the year 775 that big enough to wipe out today’s electronic system. (Solar spikes are less frequent than asteroid threats; they increase and decrease over 11 year cycles.)
TOM TIEDE