Confusing Conceptual Question on Newton's Laws of Motion

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Newton's Third Law states that for every action, there is an equal and opposite reaction, meaning that the force exerted by a person on the Earth is matched by an equal force exerted by the Earth on the person. However, the forces involved in this interaction are minuscule compared to the Earth's massive gravitational pull. The total force exerted by all humans is negligible when considering the Earth's mass and gravitational stability. Therefore, the concern that the combined forces of all people could push the Earth out of orbit is unfounded. The principles of physics confirm that the Earth remains in its orbit due to the overwhelming force of gravity acting on it.
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This conceptual question really got me thinking but I'm not sure how I would explain it:

Your friend has been studying physics. She tells you that because of Newton's Third Law, she exerts a force on the Earth opposite to the force that it exerts on her. this worries her a lot because she thinks that total force from all of the six billion people on the Earth will eventually push it out of orbit. Is she right - could this happen? Explain your answer using physics principle.

Many thanks.
 
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Gravity is symmetric in that the attraction the Earth exerts on you equals the attraction you exert on the Earth. And just as the pushback you get from the ground balances the gravitational attraction on you, the pushback your feet give to the ground balances your gravitational attraction on it.
 

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