Changes

==Planets==

==Planets==

A planet is defined as an object that orbits the [[sun]], is massive enough that its own gravity pulls it into a nearly round shape, and is dominant enough to clear away objects in its neighborhood.  <ref>http://www.nasa.gov/vision/universe/solarsystem/planetsf-20060824.html</ref>  There are 8 planets in the solar system.  They are, in order of increasing distance from the sun:<ref>The third grade</ref>

A [[planet]] is defined as an object that orbits the [[sun]], is massive enough that its own gravity pulls it into a nearly round shape, and is dominant enough to clear away objects in its neighborhood.  <ref>http://www.nasa.gov/vision/universe/solarsystem/planetsf-20060824.html</ref>  There are 8 planets in the solar system.  They are, in order of increasing distance from the sun:<ref>The third grade</ref>

*[[Mercury]]

*[[Mercury]]

*[[Venus]]

*[[Venus]]

*[[Uranus]]

*[[Uranus]]

*[[Neptune]]

*[[Neptune]]

==Dwarf Planets==

==Dwarf Planets==

A dwarf planet is an object that orbits the sun and has a round shape. <ref>http://www.nasa.gov/vision/universe/solarsystem/planetsf-20060824.html</ref> The crucial difference between a planet and a dwarf planet is that a dwarf planet is not large enough to clear the neighborhood of its orbit.  The only dwarf planet in the solar system is [[Pluto]]

A [[dwarf planet]] is an object that orbits the sun and has a round shape.  The crucial difference between a planet and a dwarf planet is that a dwarf planet is not large enough to clear the neighborhood of its orbit.  The only dwarf planet in the solar system is [[Pluto]]

==Asteroids==

==Asteroids==

There are two asteroid belts in the solar system, the one between the orbits of Mars and Jupiter, and the [[Kuiper belt]], which is in Pluto's orbit around the sun.

[[Asteroids]] are irregularly shaped chunks of rocks in the solar system.  They exist mostly in 2 places:

 

*The [[asteroid belt]], which is between the orbits of [[Mars]] and [[Jupiter]]

*The [[Kuiper belt]], which shares its orbit with [[Pluto]]

 

[[Comets]] are chunks of dust and ice.  Some are in an [[ellipse|elliptical]] orbit around the sun, meaning that they will return someday.  Some are in a [[hyperbola|hyperbolic]] orbit around the sun, meaning that they will only come into the solar system once and will never return.

==References==

==References==