What keeps the sky up?

Answer 1

The answer is gravity. Gravity is one of the forces of nature. Atoms attract other atoms. The larger the mass, the greater the gravitational force.

Since the Earth is a large mass, it attracts other matter with a relatively large gravitational force. Matter has three states besides plasma. Solid, liquid, and gas. Solids have the most density and therefore are attracted the most to Earth. These are metals and minerals such as iron and lead and rock and sand. Liquids are less dense than solids. They are also on the Earth but they tend to float on and above the solids. Gasses have the least density of matter. They are still caught by the gravity of Earth but they are able to move about above the land and water. These gasses are called the atmosphere or the sky. Heavier gasses such as nitrogen and oxygen are closer to the ground while lighter gasses like helium and hydrogen are higher in the sky. Without clouds, the sky would not appear to be an object that seems to be held up by something. It would be more easy to see it as just a bunch of gasses. Clouds can be on the ground as fog to as high as 75,000 feet or 14 miles. Earth's atmosphere gradually fades into space at about 600km or 373 miles up.

Answer 2

It's all that light from the sun and stars and neon lights which keep it up. Sky can't hardly sleep at all with all that light around, not to mention the barrage of meteors that keep hitting it.

Not to mention the heat.

Poor old Sky hasn't had a good sleep for, oh, 5 billion years.

Any wonder it gets cranky and has a hissyfit tornado/thunderstorm/ hurricane every so often?


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Okay, now for the serious answer: If by the term 'sky' you meant the atmosphere, well then it isn't held "up", but rather held down by gravity.
Otherwise the gases in the atmosphere would just drift off into space.

Answer 3

It's not so much what keeps the sky up, rather what keeps it down.

The 'sky' or more correctly, our atmosphere is composed of a mixture of gasses, these gasses have a mass so are affected by Earth's gravitational pull - it is this gravity that stops our atmosphere drifting into space thus ensuring our death!

The colours of the sky is due to complex photo effects usually regarded as the reflection of the suns light rays from the sea.

Answer 4

Are you asking, "Why does the air not fall to the ground"?

If so, the answer is, "thermal energy."

The heat from the sun keeps all the molecules in the air constantly moving fast. They constantly bash into each other, and all this bashing produces a pressure that lifts the molecules to many miles of altitude. When some of them start to fall back to earth, they are bashed again by the molecules underneath them, and bounce back up again.

If the sun were to suddenly go away, the molecules would slow down and the atmosphere would collapse, and would lay on the surface of the earth as a solid shell of (mostly) nitrogen, just a few feet thick. That would be the sky really falling!

Answer 5

The question should be, "What keeps the sky down..." The answer is gravity. The earths gravitational pull keeps the 100 miles of atmosphere around the planet. This is why the air pressure is less at higher altitudes because the gravitational pull is lower at high altitudes.

Answer 6

It is more a case of gravity keeping the sky in.
Sky gets it's colour from light reflection off the pigment of the gases in the air, and gravity stops those gases escaping into space.
The higher you travel up into the atmosphere the darker the colour of the sky becomes as less light is reflected back due to lower gravitation allowing more atoms to escape.

Answer 7

Gravity is strong enough to keep the elements in the sky from flying into space, yet weak enough that some lighter elements like hydrogren were able to escape, leaving us with an atomsphere that supports life.

Answer 8

a pair of billion Cornish Pixies..they postpone the sky from the different side, by using protecting onto tufts of the clouds and their little wings beat furiously, yet they love their interest and could by no skill enable the sky fall to the floor......

Answer 9

the sky isnt really there, theres not some big blue sheet over the earth. its just our atmosphere and the light reflecting off of it that causes it to look blue.

Answer 10

The sky is not really up.. It is us that are in fact DOWN. What keeps us down is secret tiny lead weights that are inserted into our feet at birth... and those stodgey steak and kidney puddings that come in tins (they are so dense that peas have been known to orbit around them on the plate!).