Why does a comet get pushed away by the sun when it gets too close?

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The discussion clarifies that a comet is not pushed away by the sun but rather escapes its gravitational pull due to increased velocity. As a comet approaches the sun, it converts potential energy into kinetic energy, resulting in a faster trajectory that allows it to avoid falling into the sun. The solar wind contributes to the appearance of the comet's tail, which consists of an ion tail pointing directly away from the sun and a dust tail that follows its orbital path. Misinterpretations in textbooks regarding the forces acting on comets, such as comparing them to atomic nuclei repelling each other, are highlighted as inaccurate.

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  • Familiarity with the concepts of potential and kinetic energy
  • Knowledge of solar wind and its effects on celestial bodies
  • Basic comprehension of cometary structure, including ion and dust tails
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  • Research the principles of gravitational dynamics in celestial mechanics
  • Study the conversion of potential energy to kinetic energy in orbital motion
  • Explore the effects of solar wind on cometary tails and their formation
  • Learn about the differences between ion tails and dust tails in comets
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This was shown in a textbook about the two body problem, and they compared it to the energy potential of two atoms, but the sun and comet don't experience charge so that 'when it gets too close the nuclei repel each other'.
It mentioned something about centrifugal force, but I don't understand where that comes into play.
Thanks!
 
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The comet isn't pushed away at all.

Rather, the sun isn't able to pull it strongly enough to prevent the comet from leaving the system.
 
There is a very slight "solar wind" consisting of particles expelled by the sun. That is what causes the lighter particles of a comet's tail to lag behind it. But the effect is far too small to even slow down the comet itself noticably and even the tail only "lags"- it still follows the comet around the sun.
 
I haven't checked on this but I was under the impression that the tail of a comet is not so much 'left behind' as actively 'blown away' by the solar wind?

The result being that it mostly points away from the sun rather than along the path of the comet.
 
You should be clear to distinguish between the ion tail and the dust tail. The ion tail points directly away from the sun while the dust trail rather roughly traces the orbital motion.
 
I doubt the text stated that the way in which a Meteor moves away from the Sun is similar to the way nuclei repel each other. The two nuclei repel each other due to charge but the reason why the comet moves away from the sun is because as it moves towards the sun it converts potienial energy into kinetic energy causing it to move faster giving it the velocity and centrifugal force (<there you go) to avoid falling into the sun.

Hope this helps :)
 
-e^ipi said:
they compared it to the energy potential of two atoms, ... 'when it gets too close the nuclei repel each other'.Thanks!

Sounds like a thoroughly bad book to me, throw it away.
 

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