Dan Alderson

Daniel John Alderson (October 31, 1941 – May 17, 1989) was a scientist at the Jet Propulsion Laboratory in California, and a prominent participant in science fiction fandom.

A high school science fair project on the gravitational fields of non-spherical bodies won him a college scholarship to Caltech and a job at the Jet Propulsion Laboratory, where he wrote the software used to navigate Voyagers 1 and 2.

Alderson devised a Fortran program (called TRAM for Trajectory Monitor) for navigation in the Solar System, still used by low-thrust craft in 2008.

Before he was forced to retire for medical reasons, he created a complex subroutine package (Portable NameList) in Fortran, strictly by dictation.

He organized things so well that he was able to create a number of secondary subroutines and functions, keeping all arguments in a strict order to avoid confusion.