Answer 2: A planet is usually defined as an object (which might be solid, liquid, gas, or a combination of all three) which is too small to produce nuclear fusion (which is the process by which the sun burns) and which orbits a star. read more
A planet is usually defined as an object (which might be solid, liquid, gas, or a combination of all three) which is too small to produce nuclear fusion (which is the process by which the sun burns) and which orbits a star. The Earth is an example of a planet and orbits the sun, which is a star. read more
A star is called a "sun" if it is the center of a planetary system. A large number of planets have been found that orbit other stars, thus making these stars officially "suns." Chances are that a large percentage of the stars in the galaxy also have planets orbiting them, which would make them suns as well. read more