Sun, Moon and PlanetsSo what's the problem?The planets, being close, in astronomical terms, to the earth introduce some complexity - one of which is astronomical parallax. Once this is corrected for and the LHA worked out one proceeds just as for the stars.The Sun and Moon add another factor. One needs to find the center of these bodies. However one is obliged to use either the upper or lower edge of the sun, and in the case of the moon whichever edge is available. This is known as an upper or lower limb observation and it must also be corrected for. Once the corrections are applied one proceeds exactly as one did for the stars. The moon, because it is a fast moving celestial body, is not a very easy one to get good accuracy with. The sun has other tricks up its sleeve as one can take a number of sights over a period of time and using the course and distance made good between each sight, "transfer" the intercepts and gain a fairly good position. In the same way a two-body sight, sun and moon, will give a fair position as well. Example of transferred position lines
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