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Old 12-24-2008, 11:34 AM
CC CC is offline
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How complex were the calculations for a moon shot?

Specifically, do the folks who figure out trajectories and forces, rocket timings, etc. to get an object to orbit the moon also take into account the gravity of the sun as they plan? What about the other planets? Is their pull significant?
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Old 12-24-2008, 11:53 PM
Darth Nader Darth Nader is offline
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To the Moon? No. It's a pretty big throw to get something there, but our sun really doesn't figure in there.

Last edited by Darth Nader; 12-24-2008 at 11:54 PM. Reason: Other planets? Not at all.
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Old 12-25-2008, 12:16 AM
Kevbo Kevbo is online now
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Keep in mind that the bulk of the calculations done in the 1960's were done using sliderules and trig tables. Just figuring the acceleration of a rocket that is constantly losing mass (fuel) and leaving a square-law gravity well is fairly complex when you can't approximate it with a gazillion piecewise linear segments on a digital computer. Crude as they were, the Apollo era computers were as critical to the mission success as the rocket engines.
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Old 12-25-2008, 02:02 AM
mks57 mks57 is offline
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They didn't know it at the time of the first Moon missions, but predicting lunar orbits accurately is much more complex than you might think. Due to the presence of mascons (mass concentrations), the Moon has a noticeably "lumpy" gravitational field. This can perturb the orbits of satellites in strange ways, and cause them to crash into the lunar surface far earlier than would be predicted by a simple point-source model of the Moon's gravity.
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