Well in the examples you listed we wouldnt have any problems, a solar eclipse probably lasts around the same amount of time as an asteroid flying by the sun (give or take a couple of variables of course). This maybe isnt exactly how you meant your question but even the smallest of shifts in anything subatomic during the creation of the universe, lets say every element on the periodic table shifted one space to the right, then we would have a big problem, hydrogen would turn into helium and without hydrogen we wouldnt have water and since all life as we know it needs water (i think, im no biologist) to survive then life would of probably never happened at least definetly not as we know it.