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My question may not make a lot of sense the way I've phrased it, but this is what i'm asking: what would the effect of an earth sized planet with the same orbital pattern and speed having a retrograde rotation that would be roughly the same as the standard 24 hour earth day?

I would include that there would also be a moon affecting the tides, also rotating counter to that of the planet. Would this even be possible?

I would think the tides alone would be massive and the weather patterns would cause nearly constant hurricane force winds, making it a very difficult (if not impossible) place to inhabit or colonize on a permanent basis. Or would the gravitational and tectonic forces literally rip the planet apart?


marked as duplicate by sphennings, Mołot, Azuaron, MolbOrg, Josh King May 26 '17 at 13:55

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  • $\begingroup$ If I understand correctly, the planet would be rotating east to west (earth is west to east), with a moon that orbit opposite the direction of the planet rotation? $\endgroup$ – Vylix May 26 '17 at 3:05
  • $\begingroup$ Moon based tides won't be exceptionnal. The Moon is quite slow compared to our rotation (28 days compared to 24 hours). With our current spin, the Moon is above the same longitude on Earth about every 25 hours (a bit less actually). If the Earth spun in reverse, it would make it in a bit more than 23 hours, so no big change (apart from : my answer from a similar question). $\endgroup$ – Keelhaul May 26 '17 at 8:15
  • $\begingroup$ Can you please edit your post to use proper capitalization? Also you confused effect and affect. $\endgroup$ – JDługosz May 26 '17 at 9:20

Short answer: Not much.

Long answer:

Venus has a retrograde rotation, so it's entirely possible.

The rotation would have little to no impact on tides - That'd be all up to the moon's orbit - and wouldn't cause any significant change to weather patterns. You'd see a slight difference in the length of day than if it was rotating "normally" but honestly? That's about it.

Gravity or tectonics isn't going to be affected by the planet's rotation direction, at all.

Tides are dictated by the orbital period of the moon - Whether the moon rotates normally, in a retrograde fashion, or is tidally locked like ours shouldn't have much of an effect.


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