What did Carl Sagan estimate as the top speed of a quantum turd particle?

Interestingly enough, the speed quantum turd particle is actually variable. It really depends on the distance to any nearby shart particles (or sharticles, if you will) and the weight of the actual quantum turd, as there is no one standard size found in nature. An average estimate is believed to be 10x23 kph, though like I said, it can vary greatly.