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I know that planets have a "wandering" movement on the celestial sphere. I also know that their period around the Sun vary largely as compared with the period of the Earth (one sidereal year), according to Kepler's third Law. I'm also aware though that their translation planes are closely co-planar with the ecliptic.

Hence, there must exist a pattern of their position with respect to the fixed stars on the celestial sphere.

Can someone give some links, rules or charts on how to find out the celestial path of the planets on the celestial sphere over the year(s), with respect to the constellations of fixed stars?

João Pimentel Ferreira
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  • Are you really asking about their positions with respect to the constellations, or about their positions with regard to the twelve divisions of the zodiac/ecliptic? These are very different questions. – fdb Sep 17 '16 at 00:04
  • From the perspective and point of view of someone being at the Earth, it is not the same question? – João Pimentel Ferreira Sep 17 '16 at 08:41
  • No. The signs of the zodiac are 12 divisions of 30 degrees each. They take their names (Aries etc.) from constellations, but these constellations do not overlap exactly with the 12 divisions. – fdb Sep 17 '16 at 09:12
  • Ok. Thank you for the clarification. Hence, since I suppose it would be easier to calculate and predict, I'd like to know the position with respect to the 12 divisions of the zodiac. – João Pimentel Ferreira Sep 17 '16 at 10:45
  • This is really more of an astrology question, but it's astronomical enough to belong here. What you're looking for is the ecliptic longitude, which you can compute at http://ssd.jpl.nasa.gov/?horizons, and you may also try astrological sites like astro.com –  Sep 17 '16 at 15:39
  • A key thing to note is that the different periods of the planets are incommensurate - in other words there is no repeating pattern. It is though possible to predict where any planet will be in the future. – adrianmcmenamin Sep 17 '16 at 17:51
  • @barrycarter, ok I see, you mean that I don't need the ecliptic latitude of the planet since I'm just interested in the twelve divisions of 30 degrees each for the longitude of the ecliptic, is that? – João Pimentel Ferreira Sep 17 '16 at 18:18
  • @adrianmcmenamin, take Mars as an example, there is no simple formula to find the ecliptic longitude of Mars with regards to a reference time point? – João Pimentel Ferreira Sep 17 '16 at 18:20
  • Correct. If you're just interested in constellation, you ignore the ecliptic latitude. For the Sun, the ecliptic latitude is very close to 0; for the other planets it can be quite high (as high as 8 degrees for Venus), but, since you're treating the ecliptic as "flat", this shouldn't matter. If you were viewing the planets from the sun, you could do a tolerable job of predicting the constellation. From the Earth, however, you have to take the Earth's own revolution into account, which makes things more difficult. –  Sep 17 '16 at 19:02
  • I think the model you're visualizing is something like http://astronomy.stackexchange.com/questions/12279 and http://astronomy.stackexchange.com/questions/13488 has a large list of potentially useful resources. –  Sep 17 '16 at 19:20

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