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how is the rotation and revolution of a planet that does not have a natural satellite different from a planet that has say 1 natural satellite (ex. earth and moon system).

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A body and its satellite in truth form a system and both rotate around their common centre of gravity. Hence both the Earth and Moon rotate around this centre - however because the Earth is significantly more massive than the Moon this can be approximated as the Moon orbiting the Earth.

The Moon does have a measurable impact on the Earth - tides are the obvious example, and tidal friction is also slowing down the Earth's rotation by a very small amount (around 2.3ms per century).

In the Moon's case, though, the Earth's gravitational pull has already effectively locked its rotation period with its orbital period around the Earth - so we essentially only ever see the same face of the Moon on Earth.

The Earth and Moon are much closer in mass than most other planet/satellite systems in the Solar System - think of the huge mass of Jupiter - and so it is difficult to show how these planets' satellites have a similar impact on the planet - but the same effects are there, albeit in much smaller scale.

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  • $\begingroup$ _by around a second or so every year _ More like a millionth of a second, chief. $\endgroup$ – Ricky Feb 1 '16 at 1:21
  • $\begingroup$ yes, you are right. I thought it was the main reasons for leap seconds, but it's not. Will correct $\endgroup$ – adrianmcmenamin Feb 1 '16 at 7:50
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    $\begingroup$ You'd better, otherwise someone might think that when they were building the pyramids in Egypt, each day was an hour and a half shorter. $\endgroup$ – Ricky Feb 1 '16 at 10:32

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