FrEd N EthEL N
2009-10-05 22:55:25 UTC
What is the difference between the sun and the moon?
In: Science [Edit categories]
[Improve]
The difference is simply size and composition.
The sun is a ~865,000 mile diameter ball of very light elements -- 73%
hydrogen and 25% helium. The pressure at the core is 340 billion earth
atmospheres which creates about 27 million degrees F heat -- enough heat
to cause hydrogen to fuse into helium in the core of the sun, releasing
energy and making it a star.
The moon is a ~2,200 mile diameter ball of heavy elements (oxygen,
silicon, iron, nickel, etc. etc.) left over from the formation of the
sun, as are all planets, moons and asteroids in the solar system.
Pressure at the center is nowhere near high enough to cause fusion, so
the moon is cooler and has a hard surface.
Some light elements were also left over from the formation of the sun,
and that gas was blown outward by the initial solar wind after the sun
formed. That gas coalesced into the gas giant planets, Jupiter, Saturn,
Uranus, and Neptune which are, in essence, balls of gas (mostly hydrogen
just like the sun), except they are too small to generate the core
pressure necessary to trigger nuclear fusion.
For Jupiter to become a star, it would have to be about 40 times more
massive. Then fusion would start at its core and the planet would shine
dimly ... a brown dwarf star. If Jupiter were 40 times more massive, it
would be slightly less than double its current diameter of 88,000 miles.
In: Science [Edit categories]
[Improve]
The difference is simply size and composition.
The sun is a ~865,000 mile diameter ball of very light elements -- 73%
hydrogen and 25% helium. The pressure at the core is 340 billion earth
atmospheres which creates about 27 million degrees F heat -- enough heat
to cause hydrogen to fuse into helium in the core of the sun, releasing
energy and making it a star.
The moon is a ~2,200 mile diameter ball of heavy elements (oxygen,
silicon, iron, nickel, etc. etc.) left over from the formation of the
sun, as are all planets, moons and asteroids in the solar system.
Pressure at the center is nowhere near high enough to cause fusion, so
the moon is cooler and has a hard surface.
Some light elements were also left over from the formation of the sun,
and that gas was blown outward by the initial solar wind after the sun
formed. That gas coalesced into the gas giant planets, Jupiter, Saturn,
Uranus, and Neptune which are, in essence, balls of gas (mostly hydrogen
just like the sun), except they are too small to generate the core
pressure necessary to trigger nuclear fusion.
For Jupiter to become a star, it would have to be about 40 times more
massive. Then fusion would start at its core and the planet would shine
dimly ... a brown dwarf star. If Jupiter were 40 times more massive, it
would be slightly less than double its current diameter of 88,000 miles.