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19 points rbanffy | 1 comments | | HN request time: 0.204s | source
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mrkstu ◴[] No.43669848[source]
Can someone explain the orbital mechanics of these sentences?:

The constant stretching of such tidal deformation would create friction within the planet that would soak up some of its orbital energy, causing it to edge closer to the star.

How exactly does the energy of tidal energy being expressed inside the planet affect its speed relative to its host star? There is no external friction in empty space so how does the speed disappear?

replies(2): >>43670071 #>>43671631 #
1. solid_fuel ◴[] No.43671631[source]
The energy is lost as heat - as the planet flexes some pieces are moved in opposing directions by the tidal forces. Those pieces rub against each other, transforming the gravitational energy into heat.