Things usually happen pretty quick in the world of flybys, and we have two back-to-back next week. So literally every second counts, on Monday, we are going to race past Ganymede at almost 12 miles per second( 19 kilometers per second). Less than 24 hours later we're performing our 33rd science pass of Jupiter -- screaming low over the cloud tops, at about 36 miles per second( 58 kilometers per second). It is going to be a wild ride.