Why aren't the Moon and the Sun planets?

Question

Is there a reason to why the Moon and Sun aren't planets? I hope you teach me why. Thanks! I really appreciate it.

Answer 1

Cosmo got it right except the part about the Moon being a moon. The Moon is a satellite, "Moon" is just our name for it, no other planet or body out in space has a Moon, they are all satellites that orbit them.

Answer 2

The sun in not considered a planed because it is an energy source .  A sun or star is considered the center of a planetary system basically a life generator through the energy thrown out  from its surface into space and collected by the planets.  Humans have classified the masses within a planetary system and as we have seen with Pluto we can change their classification at will.  Basically the size of the subject and wither it orbits another object.  Some of the moons orbiting Jupiter may be able to promote life in some form so that does not seam to enter into the calculation.

Answer 3

The moon is big enough to be a planet if it was in its own orbit, but since it orbits the Earth, it's a moon. The sun is not a planet because it's a star. Stars can't be planets, even if they are in orbit around another star.

Answer 4

The Sun is a star.

The Moon is a moon, because it orbits the Earth.

If the Moon orbited the Sun and not the Earth, it would be a planet---planet Mercury is about as big as the Moon.

Answer 5

the sun is not a planet because it has planets revolving around it, its a star.

the moon is not a planet cause it revolves around one, its a satellite.

planets are called planets cause they revolve around stars. they dont need to have satellites(moons) to be planets but they do sometimes.

Answer 6

Originally, the Moon and the Sun were planets.  There were seven - also including Mercury, Venus, Mars, Jupiter and Saturn.  The days of the week are named after these objects.  Sunday, Moonday, Marsday, and so on.

At that time, a planet was something that wanders through the sky.

The Earth was not a planet.

But now that something is known about the planets, it's pretty clear that the Sun and the Moon are in a different class, and the Earth more closely resembles the other large orbiting bodies.

We like to classify things that are similar to each other.  But Earth has little in common with Jupiter.  What we really have are terrestrial planets - Mercury, Venus, Earth, the Moon and Mars.  The gas giants - Jupiter, Saturn, Uranus and Neptune.  A bunch of pretty big round objects like Ceres, Pluto, Eris, etc. And minor planets which are smaller objects.  And of course, stars like the Sun.

Answer 7

the sun is a star with all types of gases in it it's like a special star.

the moon is just a moon.

Answer 8

the sun is star, a ball of gas that has a core that ungoes nuclear fusion to produce energy (planets dont do that)

the moon is on the small side and it orbits the earth.

Answer 9

Because the sun is on fire, and planets aren't on fire.  That particular trait belongs to stars.  Also, the moon is too small to be a planet or even a planetoid.  That's why moons are classified as moons.  And planets don't generally revolve around each other.

Answer 10

PLANETS ARE NAMED BECAUSE OF CHARACTERISTICS THEY SHARE. ONE OF THE CHARACTERISTICS IS THAT THEY ORBIT A LARGE STAR LIKE THE SUN, SO THE SUN CANNOT BE A PLANET. SECOND, MOST PLANETS IN OUR SOLAR SYSTEM HAVE MOONS WHICH ARE SMALLER BODIES, SO THE MOON CANNOT BE A PLANET.

THIRD, THE PLANET MUST HAVE CERTAIN MEAUSERMENTS TO FIT THE DEFINITION OF A PLANET ,THAT IS ANOTHER REASON WHY MOONS ARE NOT PLANETS AND SOME OTHER PLANETARY OBJECTS A KNOW AS "DWARF PLANETS" AND NOT PLANETS.

hope this teaches you alot and if you still dont understand ask more questions!

thats how we learn :)

Answer 11

Because they don't fit the definitions.  Kind of like asking, "Why isn't a turtle a bird."

Doug