When data from Jupiter's moons was used in 1671 to determine accurate longitude (along with latitude) of positions along the French coast, it was found that the area of France was significant smaller than previously thought. Upon seeing the new and more accurate maps, Louis XIV is said to have exclaimed, "I have just lost more territory to my astronomers than to all my enemies."
Rick Strickert
Austin, TX
-----Original Message-----
From: phys-l-bounces@carnot.physics.buffalo.edu [mailto:phys-l-bounces@carnot.physics.buffalo.edu] On Behalf Of Philip Keller
Sent: Friday, March 19, 2010 7:45 AM
To: 'Forum for Physics Educators'
Cc: Robert Amitrani; Edward Kinch
Subject: [Phys-l] physics history puzzle
So I just read this and I thought it was really interesting. I'll make it a puzzle:
Whenever I teach Roemer's method for finding the speed of light, I am always amazed that anyone in that era would time the orbits of Jupiter's moons so carefully. But know I know that the timing of those Moon's was a potentially important and relevant matter at that time for a reason unrelated to the speed of light but with potential for great economic and military implications...