For the greater beauty of the instrument, the balls representing the planets are to be of considerable bigness; but so contrived, that they may be taken off at pleasure, and others, much smaller, and fitter for some purposes, put in their places.

Rittenhouse was the perfect person to study the mysterious planet as he had a personal observatory on his family farm. In 1763 Mason and Dixon began a survey of the Pennsylvania-Maryland border but this work was interrupted in 1767. Hannah survived David by more than three years dying in late 1799.

David Rittenhouse (April 8 1732 – June 26 1796) was a renowned American astronomer inventor clockmaker mathematician surveyor scientific instrument craftsman and public official.