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Ancient Astronomical Computer Decoded
slimjim8094 writes "A mechanical device from 150BC was found in a shipwreck. Upon examination with X-Rays, the device appeared to be a revolutionary computer used to calculate lunar cycles. This device "is technically more complex than any known for at least a millennium afterward." From the article
"The hand-operated mechanism, presumably used in preparing calendars for planting and harvesting and fixing religious festivals, had at least 30, possibly 37, hand-cut bronze gear-wheels, the researchers said. A pin-and-slot device connecting two gear-wheels induced variations in the representation of lunar motions according to the Hipparchos model of the Moon's elliptical orbit around Earth."
NPR radio said that it appeared in Greek literature that other complex devices were used by the wealthy to amuse guests.
Currently I have a Nixie clock for the same 'guest amusement' function. In several millennium when this creation is rediscovered it will seem oddly complex and mysterious. Bill Gates and Scott McNealy, what mysterious technical devices are in your living room?
So whats a Nixie? Forgot already have we? Jeff Thomas and Laurence Wilkins build good Nixie clocks.
http://www.amug.org/~jthomas/clockpage.html
Cheers,
Jim Burke
It is not clear to me if the sophistication label given to it is due to the mechanics or the math. It appears to be in the math rather than so much the mechanics. But that is not surprising since the ancient greeks put more stock in math than mechanics. They didn't need mechanical devices because they had slaves.
Table-ized A.I.
Just make a search on De Solla Prices diagram of the antikytheras.
Simple math that we all can understand.
The sun gear has 64 teeth.
It meshes with the smaller of a 38,48 gear pair.
The 48 meshes with the smaller of a 24,127 gear pair.
The 127 meshes with the 32 teeth of the moon gear.
The ratio of angular speeds can then be calculated as (64/38) x (48/24) x (127/32)=(254/19) = 13.36842..
which is an excellent approximation of the astronomical ratio 13.368267..
This corresponds with the Metonic cycle, in which 19 solar years correspond exactly with 235 lunations,and therefore with 254 sidereal revolutions of the Moon.
Thus. for every 19 (direct) turns of the main drive wheel; this produces 2,356/2 revolutions of the whole differential turntable, and all the gears mounted upon it.
This is just awsome. You can pin point where the moon will be located, just by turning one wheel a certain number of time, according to what year is it. Thus, you can tell what the tide will look like days, weeks, months ahead of your trip at sea.
How come this device died and disapeared for centuries? Given the Egyptians knowledge of the earths equinox, this was the key to discover America way before Colombus did.
I know you're joking, but given the fact that we're finding old stuff based on some pretty intense knowledge, I'm starting to think that Graham Hancock might be right about us being older, as a race, than we think we are. He attracts a lot of criticisms, but mostly from egyptologists because his interpretations of artifacts found contradict theirs. The book is an excellent read though.
Though aliens would be fun too, I suppose...
Oh god, that woman is John Romero!