I always wondered why isn't the Earth shrinking or melting because of the core.

  • $\begingroup$ Why do you think it should collapse? $\endgroup$
    – Virft
    Nov 30, 2016 at 18:14
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    $\begingroup$ Possible duplicate physics.stackexchange.com/q/15169/24774 $\endgroup$
    – fffred
    Nov 30, 2016 at 18:39
  • $\begingroup$ Core means the central or middle part of something. Most things have a core, but it doesn't necessarily make them collapse. $\endgroup$ Nov 30, 2016 at 18:52
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    $\begingroup$ @sammy: methinks OP is intending to ask about the (extreme) temperature of the core and not its existence, as you are implying there. $\endgroup$
    – Kyle Kanos
    Nov 30, 2016 at 19:16
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    $\begingroup$ Its pretty obvious that the Earth is not shrinking or melting into the core, because we can observe that it isn't. Questions like this are really centered around the fact that you have a mental model of how the world should work that is not correct. Good news: you've noticed this oddity and you decided to ask for help. Bad news: we really need you to explain why you think the earth should shrink/melt because we need to understand what your mental model actually is before we can really help you improve it. We need more than a few words to do that. $\endgroup$
    – Cort Ammon
    Dec 1, 2016 at 0:44

1 Answer 1


Gravity pulls material towards the centre, whereas heat (the kinetic energy of the particles) causes pressure which enables matter to resist being compressed. The two forces are balanced. If one were greater than the other, the Earth would contract or expand until balance is reached.

The same balance between pressure and gravity keeps stars (which are a million times more massive than the Earth) from collapsing.


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