Timeline for Earth rotation: What provides the energy?
Current License: CC BY-SA 4.0
13 events
| when toggle format | what | by | license | comment | |
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| Sep 25, 2020 at 12:41 | comment | added | dominecf | @DescheleSchilder Sun definitely influences axes of rotation of all planets (e.g. causing about 1/2-hour difference between two definitions of year on Earth, sidereal and synodic one). But the peculiar cases of Venus and Uranus are attributed to some massive impact. | |
| Sep 25, 2020 at 12:38 | comment | added | dominecf | @TonyK finding heights of Moon/Sun tide is the beginning; computing the realistic dynamics of this three-nearly-solid-body system would be a bigger feat. Generally, all this modelling also depends on WHEN and HOW we set up this thought experiment. Note for instance that with current settings, in some 2-3 billions years Moon will drift from Earth so much its tidal influence will halve. | |
| Sep 25, 2020 at 12:25 | comment | added | Deschele Schilder | @TonyK You are right. I didn't search at all. My mistake. I was reasoning from the perspective of the planets only, without taking into consideration their moons and interaction with other planets. Is the Sun somehow able to change the direction of the rotation this type of planets? Maybe if the Sun reverses its rotation direction? But how can this be done? What do you mean by serious research? | |
| Sep 25, 2020 at 12:15 | comment | added | TonyK | @dominecf: lunar tides are more than twice as strong as solar tides. (I didn't need to do any "serious research" to find this!) | |
| Sep 25, 2020 at 12:08 | comment | added | dominecf | @DescheleSchilder ... not really, some planets rotate in a weirder way; please refer to en.wikipedia.org/wiki/Axial_tilt | |
| Sep 25, 2020 at 12:04 | comment | added | dominecf | @TonyK maybe non-rotating Earth would tidally lock to Moon as you wrote. Maybe it would tidally lock to Sun instead and rotate once a year. By accident, both tidal effects are of similar magnitude on our planet. I did not make serious research which one would prevail. | |
| Sep 25, 2020 at 11:34 | comment | added | Deschele Schilder | Also note, that if the Moon weren't there, life on Earth would probably have not evolved. Also, all planets rotate in the same direction. Also +1. | |
| Sep 25, 2020 at 10:46 | comment | added | Oscar Bravo | @BЈовић An asteroid or comet impact could also impart angular momentum (positive or negative) to the Earth. Something that came in tangentially, near the equator would have the greatest effect. If it came straight "down" (if its direction vector passed through the centre of the Earth), it would have no effect. A nice exercise in vector algebra... | |
| Sep 25, 2020 at 9:34 | comment | added | TonyK | @BЈовић: Yes. If we started from a situation where the earth was not rotating and the moon was in its present orbit, then tidal forces would cause the earth to start rotating, until its rotation was synchronous with the moon's orbit. (This would take a very long time!) | |
| S Sep 25, 2020 at 8:58 | history | suggested | Graham | CC BY-SA 4.0 |
Fixed typos.
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| Sep 25, 2020 at 8:18 | review | Suggested edits | |||
| S Sep 25, 2020 at 8:58 | |||||
| Sep 25, 2020 at 8:02 | comment | added | BЈовић | can they also speed the rotation up? | |
| Sep 24, 2020 at 20:10 | history | answered | gandalf61 | CC BY-SA 4.0 |