Voyager 1 sending again!

[Maximilian Hohmann]

Hello!

(04-24-2024 04:11 PM)Roland57 Wrote:  Johannes Kepler didn't invent a calculating machine ! It was Wilhelm Schickard, who built the first calculator in 1623, this machine has been destroyed by a fire. He described the machine in a letter to Keppler 1624. Schickard's drawings of the machine have been lost for centuries. They have been discovered in 1960. Engineers built a working replika based on these drawings.

As written above, I live in the same town as Wilhelm Schickard, who was a professor for Hebrew and astronomy at the University of Tübingen. So I must do some nitpicking now ;-)
Schickard built two of his calculating machines around 1623, one for himself and one for Johannes Kepler. Both were destroyed by fire a few years later and Kepler never received his machine. But some letters written about it to Kepler survived the centuries, which included drawings of the workings of the machine. These letters were unearthed and published in the early 20th century but remained mostly unnoticed until the mid 195ies.

Based on these drawings, Bruno von Freytag-Löringhoff, then professor emeritus for philosophy at the same university as Schickard but 300 years later, personally built a replica of the machine at his home using amateur tools.
Schickard's drawings are not very precise and Freytag only fully understood the working principle after it was revealed to him in a dream. Really, no kidding! Freytag-Löringhoff personally told this story to one of my astronomer colleagues who used to play chess with him. He bulit two replicas, one is here in Tübingen in the town museum ("Stadtmuseum" - free entrance! and you are allowed to touch and work the machine) and the other at the "Arithmeum" in Bonn. But there are more replicas in other museums built by different people, occasionally one keeps popping up at eBay for a ridiculous asking price of 49.000 Euros. If you make one yourself you spend maybe 50 Euros for wood and brass.

Some people say that, had Kepler ever received his calculating machine, the progress in astronomy would have gained at least a century. Because at that time, astronomers like Kepler wasted 95% of their working time performing stupid routine calculations by hand in order to compile their tables and almanachs. If he could have spent that time looking forward, who knows what discoveries he could have made.

Different from the machine of Pascal, which could only add and substact, Schickards machine included a section with devices like Napier bones used for multiplications. It was not a true multiplication machine, but combined the adding/substracting machine and a crude predecessor of the slide rule (which was invented only ten years later) in the same housing.

Regards
Max

NB: I am quite sure that the trajectories of the Voyager spacecraft could have been worked out without computers and calculating machines, using only pen, paper and slide rule. But without an onboard computer to steer the spacecraft, collect data and images and send them to Earth the mission would have been quite pointless.