Revolution of Planets: Rotation & Revolving Around Stars

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Planets continuously rotate on their axis and revolve around stars due to the conservation of angular momentum and gravitational forces. They do not consume energy for this motion; instead, their spin energy remains constant while their orbital kinetic energy fluctuates with changes in gravitational potential energy. Since there is no friction in space, planets do not lose energy or slow down over time. Consequently, they do not expel heat as a result of their motion. The mechanics of planetary motion are governed by fundamental physical laws that ensure their continued rotation and revolution without energy consumption.
saket agrawal
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How do planets continuously rotate on their axis or revolve around stars ? Do the energy they consume for this continued motion gets expelled as heat ?
 
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saket agrawal said:
How do planets continuously rotate on their axis or revolve around stars ?
Explain to yourself how they can not.
 
saket agrawal said:
How do planets continuously rotate on their axis or revolve around stars ? Do the energy they consume for this continued motion gets expelled as heat ?
No energy is consumed for this. A planet in orbit has constant energy: its spin energy is constant, and its orbital kinetic energy changes by the opposite amount that its gravitational potential energy changes.

Also, if they were consuming energy (which they are not) then they would have to absorb heat (which they do not). Expelling heat would be exactly backwards.
 
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There's no friction, so nothing slows down planets. Gravity do not "consume" any energy
 

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