Through his work on the educational aspects of the Fox satellites, Mark Spencer has produced some great experiments and materials. The Fox-1 attitude determination experiment, and now the Fox-2 MPPT system have both been presented in the AMSAT Journal. If you aren't a member of AMSAT you are missing some great stuff in the Journal.
But in this research and work for the Fox-2 MPPT system I believe that Mark may have inadvertently answered an age old question that has (to my knowledge) never been definitively been answered before. A question as old as the icebox itself. In the MPPT article figure 3, Mark presents a measure of voltage and power in three environments: a room (presumably in his home), the refrigerator compartment of his refrigerator, and the freezer compartment of his refrigerator. The measured power is higher in the refrigerator and even higher in the freezer.
EUREKA! I believe that Mark has finally proven that the light in the refrigerator (or freezer) STAYS ON WHEN THE DOOR IS CLOSED! Otherwise, how could there have been any power output in the refrigerator or freezer at all? A solar panel requires light to work.
Thank you, Mark! I can now share with my mother (poor Pop isn't around to enjoy this discovery although he first posed the question to me 50+ years ago) that I KNOW.
And keep up the good work that you are doing for the ARRL Education and Technology Program too.!
73 Jerry N0JY
(The above was for fun and in no way meant to diminish Mark's work.)