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Is there a table which shows the dates of the planets retrograde motion? I want to know at which date a certain planet will start the retrograde motion.

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  • $\begingroup$ This might be a duplicate - check this out: physics.stackexchange.com/questions/249493/… $\endgroup$ – MystaryPi Aug 26 '18 at 21:56
  • $\begingroup$ @MystaryPi Unlike Physics and Chemistry, the rest of Stack Exchange does not consider a question to be a duplicate if it is asked in another community. It may be considered a cross-site duplicate if it is asked by the same user, but there is no path to close such a question as a duplicate. In this case, this question has not been asked by this user before, so unless there is a duplicate on Astronomy this question should not be closed. $\endgroup$ – called2voyage Aug 28 '18 at 13:21
  • $\begingroup$ Oh okay, thank you for informing me on that! I'm still getting used to how this site works (I've only been here for around 2 weeks). I'll be sure to see if it's an ACTUAL duplicate next time. $\endgroup$ – MystaryPi Sep 2 '18 at 15:29
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There is an annual publication "Astronomical Phenomena for the Year YYYY" published by the United States Naval Observatory and United Kingdom Hydrogrphic Office. Page 6 of the 2018 edition gives a table of conjunctions, stationary, oppositions, etc. for the planets. See http://aa.usno.navy.mil/publications/reports/ap18_for_web.pdf

For the superior (outer) planets, the earlier stationary date is when it starts its retrograde motion. The second stationary date is when it ends its retrograde motion.

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EDIT: It turns out calsky.com will do these calculations for several years out, including other calculations commonly found in almanacs. Sample page:

https://www.calsky.com/cs.cgi?cha=7&sec=6&sub=3

The best place to start on this site isn't the home page, but rather the TOC:

https://www.calsky.com/cs.cgi/TOC?&f=

I now consider my answer to be better than @JohnHoltz's :)

Note: I saw @JohnHoltz's answer while I was typing out my answer, so some of the below may be redundant. Upvote/checkmark his answer, not mine.

This isn't really an answer, but too long for a comment:

  • I was disappointed how difficult it was to find this information, given how easy it is to calculate and how many other astronomical phenomena are listed in various places on the Internet.

  • When a planet starts or ends retrograde motion, it is temporarily stationary before it "turns around". Thus, some astronomical sources will say "Jupiter stationary" instead of "Jupiter starts retrograde motion".

  • Based on the above I google'd "jupiter stationary" "mars stationary" (as quoted; google tries to correct one of the stationary's to stationery, so I had to click one more time to do the search correctly), and finally found something: http://aa.usno.navy.mil/publications/docs/ap.php

  • The publication doesn't mention retrograde, but it does mention when a given planet is stationary and provides a brief description of each planet's position in the sky for the given year.

Because this seems like a fairly easy calculation to make, I may do it myself and update this answer.

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  • $\begingroup$ I was looking for such a site to calculate the phenomena, but I could not find it. CalcSky is an obvious solution :-) $\endgroup$ – JohnHoltz Aug 27 '18 at 21:29
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Check this website out - it has a table that might help you: Website

Or you can look here.

This site is also a little sketchy (it's for horoscopes and stuff) - but it still has some accurate information on the exact dates of retrograde: Website

Hope that helps!

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  • $\begingroup$ I'm pretty sure Mercury has a retrograde period, so I'm curious about the empty entry. $\endgroup$ – barrycarter Aug 27 '18 at 16:46
  • $\begingroup$ Yeah, I was confused about that too. That's why I added the other site for more info. $\endgroup$ – MystaryPi Aug 27 '18 at 18:14

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