New Delhi, April 22 (IANS). Have you ever wondered why our Earth as well as all the planets present in space are round? Why aren’t they cube, pyramid or any other shape? It is directly related to gravity, which plays an important role in determining the shape and structure of every object in the universe.
Gravity pulls every planet equally from all sides, due to which their shape becomes round like a ball. All the planets in the solar system are of different sizes and shapes. Some are small rocky and some are huge gaseous. But they all have one thing in common, they are all round. Whether they are small or big.
Gravity is the force that forces the planets to become round and not cube, pyramid or any other shape. Without gravity, no big body in the universe can become round.
American space agency NASA gives detailed information about this, according to which, dust, gas and small stones keep colliding with each other in space. Gradually these pieces come together. When a large amount of matter accumulates in them, they develop their own gravity. This gravity becomes so strong that it pulls all the small pieces around towards itself. When the planet becomes big enough, it sweeps up all the particles in its path.
Gravity pulls equally in every direction from the center of the planet. Just like the spokes of a bicycle wheel pull from the center to the edges. Due to this equal stretching, the shape of the planet becomes like a three-dimensional sphere. If any part is protruding, gravity pulls it inwards. It is through this process that planets become spherical.
The special thing is that not all planets are completely round. Most planets are fairly round, but some have slight variations. Mercury and Venus are the most spherical, having almost perfect sphericity. Little difference is seen in the giant gas planets like Jupiter and Saturn. They rotate very fast on their axis. Due to rotation, the part near their equator bulges slightly outwards. This is called ‘equatorial bulge’ or equatorial bulge. When something rotates faster, its outer parts have to move faster. Gravity continues to pull it in, but the force of rotation pushes it outward. Saturn is the most prominent, with its equator 10.7 percent wider than its poles.
Whereas in Jupiter it is 6.9 percent. These look a little flat, like basketballs. Earth and Mars are small and rotate slowly, so there is very little bulge. Earth’s equator is only 0.3 percent wider, while Mars’s is 0.6 percent. Uranus at 2.3 percent and Neptune at 1.7 percent are in between.
–IANS
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