Lots happening on the Hudson during this incredible extended summer — including stunning, contrasting examples of power.

On a recent photo excursion, we spotted the tail section of a submarine, possibly on its way to the NAVY shipyard in Groton, Connecticut. Will it be a ballistic missile sub, or an attack sub? Check out this piece from Undersea Warfare on how they put one of these together.

A little less intimidating — but no less exciting — was a visit from the BayCycle Project. Founder Judah Schiller straps two pontoons to his bike, which powers a propeller and pushes him across the water. In late September, he became the first person to bike across the San Francisco Bay, and last week, the first to pedal across the Hudson — without the help of a bridge, of course.

Nearly all U.S. submarines are nuclear powered. Schiller runs on elbow (knee?) grease. Quite the contrast of high-tech versus low-tech power.