It's hard to believe, but nearly every day within the narrow confines of the Houston Ship Channel (HSC), massive commercial vessels (some in excess of 80,000 deadweight tons) engage in a hydrodynamics dance face off. When two of these vessels meet bow to bow within the HSC (one heading inbound, the other outbound), they head directly at each other generally closing at a rate exceeding twenty knots (about 23 miles per hour). At a separation distance of about one-half mile, each turns four degrees or so to its starboard (or to the right for landlubbers out there). When both bows start to pass each other, the Houston Pilot aboard turns back to port (or left) to bring his or her respective vessel parallel to the other, and then as each vessel passes the other's stern, turns further to port and then back to starboard to resume transiting down the center of the narrow HSC.