Planetary conjunction

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jimhebert United States of America
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Planetary conjunction

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Post by jimhebert »


What is the maximum degrees of separation between 2 planets before they are in conjunction? Is there a formula using RA and Declination or an online calculator that is reliable? :text-thankyouyellow:
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Thefatkitty Canada
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Re: Planetary conjunction

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Post by Thefatkitty »


This may be of interest:What is a planetary conjunction?

Hope that helps and all the best,
Mark

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jimhebert United States of America
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Re: Planetary conjunction

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Post by jimhebert »


Thank You.
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Baurice
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Re: Planetary conjunction

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Post by Baurice »


I thought the official definition was that a conjunction is when two objects have the same RA. This happens at a very exact time. Quite often I photograph "conjunctions" where the RA is about a degree or two different. You can even photograph two planets close together or a planet and bright star with just a phone camera. Here is a recent example:

jimhebert United States of America
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Re: Planetary conjunction

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Post by jimhebert »


I see. I had read somewhere that if the planets were 8 degrees apart they were considered to be in conjunction. If greater than 8 degrees apart they were not in conjunction. I don't know what the rule is.
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JayTee United States of America
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Re: Planetary conjunction

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Post by JayTee »


This quote comes directly from the Greenwich Observatory, London, UK. So I would say this is the definitive answer!

"If two objects have the same right ascension or the same ecliptic longitude, they are considered to be in conjunction with one another."
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jimhebert United States of America
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Re: Planetary conjunction

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Post by jimhebert »


Thank You. That settles the issue.
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