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General => Open Discussion => Topic started by: archonforest on November 17, 2019, 09:52:13 AM

Title: Moon question-something is weird
Post by: archonforest on November 17, 2019, 09:52:13 AM
Hope there is someone here who can answer this question. Yesterday I got out of the house at 7:30am and the moon was on the horizon front of me. Now today morning I left the house again at 7:30 and the moon was way up to the left like 35 degrees compare to yesterday. This is a very big change in a very short time. Is this make sense?
Title: Re: Moon question-something is weird
Post by: Ariel DK on November 17, 2019, 11:00:09 AM
Congratulations! you have noticed the moon's Relative Translational motion

I'm pretty sure that this displacement was to the east, or nearly, right? the Moon has an average relative motion of 13 degrees per day to the east.
Is called "Relative"  because the Moon's eastward motion is much slower than the sky's westward motion, so though moving to the east from day to day, it still has a net motion toward the west each day. this means that it still rises in the east and sets in the west like the stars, but a little later each day.
Title: Re: Moon question-something is weird
Post by: archonforest on November 17, 2019, 12:09:17 PM
Wow! Thx for solving this. :)
I learned something new again.
Title: Re: Moon question-something is weird
Post by: WAS on November 19, 2019, 01:26:08 PM
Must be relative to your position on earth. Here in the WA in northern hemisphere it's shifted about 5 degrees east every night, nothing so significant. It does this for well over a month before it's zenith moves to daytime.
Title: Re: Moon question-something is weird
Post by: penboack on November 19, 2019, 09:11:42 PM
The moon takes 28 days to orbit the Earth, so 28 days to do 360 degrees which is 12.8 degrees per day.
I got a spectacular view of it in the fork of a tree trunk earlier tonight.