Why planets are almost spherical in shape?

I always wonder why the planets are spherical in shape and not any other shape like cuboid/conical/cylindrical in shape???If the Earth had been formed due to big bang explosion i.e., a part of some other huge celestial body, why it is not in any irregular shape? If it had some other shape before, how did it get the present shape?

Please do answer these..........Thanks

3 Answers

  • 8 years ago
    Favorite Answer

    Gravity is the cause. Everything with mass has a gravitational pull. The more mass an object has, the more it will pull all of its parts toward each other.

    A planet, as defined by the International Astronomical Union, must be massive enough to be roughly spherical by its own gravitation (it must have reached hydrostatic equilibrium). The Earth has enough mass for this but not enough to completely round it out. There are mountains and valleys and on the ocean there are large waves.

    Compare Earths shape to:

    ~ An asteroid. It has such a small amount of material that the total gravitational pull is not strong enough to crush it into a ball. Asteroids look lumpy, similar in shape to potatoes.

    ~ A neutron star. More massive than our sun but only about 12 kilometers in diameter, its surface gravity is so strong that it has no hills or valleys. The entire surface is smoother than a sheet of glass.


  • 8 years ago

    Because the sphere is the most stable state a planet could be in. And the gravity of the planet's core compacts it into a spherical shape

  • ?
    Lv 7
    8 years ago

    Gravity... look it up

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