Why are all planets round?
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Why are all planets round?
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You asked us, "Why are all planets round?"

In a nutshell? Gravity.

We all know what gravity is, right?

It's what makes apples tumble from trees and people fall flat on their faces, and,
well, the bigger an object is, the stronger its gravitational field.

Planets are pretty big, so gravity acts on them as a strong force, pulling everything together towards their center and the resulting shape is a sphere.

Now, planets aren't actually perfectly round - they've got a bit of what you might call a spare tire.

You see, planets spin around their axes and the force generated by the spinning works against gravity and causes a planet to bulge out at its equator.

Join the club, planets.

Source URL: https://www.tweentribune.com/article/tween78/why-are-all-planets-round/

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CRITICAL THINKING QUESTION
Why aren't planets perfectly round?

• batiar-3-bar
12/04/2015 - 09:09 p.m.

Planets are round because the bigger an object is the more gravitational pull the object has. With the planets having such a large gravitational pull it reacts with them turning into a spheric shape. While the planets are a spheric shape they turn, which goes against gravity, causing them to pop out at the equator and make them not perfectly round. I found this article very interesting because I had never thought about why the planets are in a circular shape and now knowing it's the gravitational pull to the center of a planet I feel more educated. In my opinion gravity is quite amazing in the way it works and how it's what holds things together and what makes them fall apart. I think after reading this article I will definitely be enthralled to learn more about gravity and how it affects everything around us.

• nathanr-ver
12/06/2015 - 04:02 p.m.

The planets aren't perfectly round because they are always spinning on their axis.

• tonyw-1-ver
12/07/2015 - 08:43 a.m.

Planets are pretty big, so gravity acts on them as a strong force, pulling everything together towards their center and the resulting shape is a sphere.

• austonh-phi
12/07/2015 - 02:16 p.m.

Planets aren't perfectly round because of their axis. After spinning for many long years it bulges the equator of the planet that's spinning. Gravity is pulling the planet causing the equator to bulge making the planet to lose its sphere shape.

• tjg-phi
12/07/2015 - 02:26 p.m.

Planets are round due to gravity. Since planets are huge they have a strong gravitational pull. Since the gravitational pull is so strong it pulls everything towards the planet's center resulting in the planets circular shape. Planets aren't perfectly round due to the spinning of the planet's axis. The force from the planet's spinning on its axis works against gravity causing a bulge at the planet's equator.

• tyn-2-bar
12/08/2015 - 12:23 a.m.

Planets aren't perfectly round because they spin around their axes. In the article it says "planets spin around their axes and the force generated by the spinning works against gravity and causes a planet to bulge out at its equator.". When planets spin they cause something called "centripetal force". What this does is causes the matter in the planet to move in a curved path as far from the center as possible. But, gravity pulls the matter towards the center of the planet. Therefore, the planet is left with an almost perfectly round shape.
I just figured that out now and I realized how interesting science is once more.

• christinaz-mcc
12/09/2015 - 11:34 a.m.

Planets are perfectly round because gravity is pulling everything towards the center making the planets round.

• nolann-mcc
12/09/2015 - 11:35 a.m.

Planets are not perfectly round because of the difference in gravitation pull. The difference is that gravity tries to be as even as possible but their is always and off set. Also when your pulling thing toward you it is difficult to take the shape of a perfect circle.

• trentons-hor
12/09/2015 - 03:00 p.m.

I think the authors purpose was to inform the reader. Gravity pulls every thing into it, but it not perfectly round because the planet spins around their axes and force generated by the spinning works against gravity and causes it to bulge out of the equater

• mayaw-6-bar
12/09/2015 - 11:48 p.m.

Planets aren't perfectly round because they spin around their axes. In the video, the man states that,"You see, planets spin around their axes and the force generated by the spinning works against gravity and causes a planet to bulge out at its equator." I chose this article because I already knew planets weren't perfect spheres, and I wanted to know why that was. I found this article interesting because I got to know the reasoning behind why planets are not perfectly round. My personal opinion is, that anything found in nature is not perfect, just the way planets are not perfect spheres.