Memorizing numerical facts is not merely about speed of calculation, but also about instant recognition, which helps in deciding which branch to take at a fork in the road. It could also be a tie-breaker in a hiring situation. Other things being equal, which candidate would you hire: the one who knows the value of pi to 2 decimal places, or the one who doesn’t.
You can be at most a half world away for the same reason that a dog can run only halfway into the woods.
The correct cosmology is given by Dewey B. Larson.