Mass of the earth

I awoke this morning with the formula Newton used to determine the earth's gravational attraction to objects (actually Cavendish's formula he used to find the mass of the earth). G=m1*m2/d^2 Why would I have that in my thoughts? What is even more bizarre is that I actually remember the mass of the earth 5.979 x 10^24 kg but the distance to the moon eludes me. Then to really freak myself I spontaneously pulled the formula for volume out of my butt, no joke. 4/3 pi r^2 baby. Ok smarty pants I say, I bet you don't remember the radius of the earth. No shit, like 30 seconds later I remember 6.3713x10^4 meters and that makes the volume 1.0 and change x 10^15 meters cubed. How the fuck did I calculate exponents in my head and how did I remember all those constants? I know what this means now...I said in physics class that once I began to understand physics, those physics would cease to exsist in the world as we know it. Oh shit, the end is coming. However, it is very cool to have a moment of complete memory recollection. THAT will never happen again. It was like a moment of clarity, I could think without hinderance.

Now I can't even remember the combo to my gym locker that I use everyday. But the density of water at room temperature is approximately 998.23 kg/m^3. Go figure...:/