What planets exist in our solar system?

We used to know of 9 planets in our solar system:

Mercury Venus Earth Mars Jupiter Saturn Uranus Neptune and Pluto

You can use a mnemonic to remember the order of the planets. That is a phrase or sentence comprised of words which start with the same letters as what you wish to remember.

My favourite was: My Very Educated Mother Just Served Up Nine Planets

Though of course this only works whilst there are nine!

Here are some others:

Many Very Elderly Men Just Snooze Under News Papers

Make Very Easy Mash - Just Squash Up New Potatoes

Many Vicious Elephants Munch Jam Sandwiches - Unusually, No Peanuts

Mary's Violet Eyes Make John Sit Up Nights, Pining

and ... My Very Excited Mouse Jumped Straight Up Nanny's Pants!!!

Then we started finding other objects out past Pluto, and one of them appeared to be bigger than Pluto, so it Pluto was a planet, then this other object had to be one as well.

So in August 2006, at the conference of the International Astronomical Union - held every 3 years - a definition was adopted which effectively said:

The 8 main planets run from Mercury to Neptune.

In addition, three objects were designated as dwarf planets. They were Pluto, the new large object beyond Pluto which was given the official names of Eris, and Ceres - the largest of the asteroids between Mars and Jupiter. The reason for including Ceres was that, unlike the rest of the asteroids, it has sufficient mass so that it's gravity has drawn it into a round shape, which is one of the criteria.

Since then, two other objects between Pluto and Eris and been designated as dwarf planets - they are Haumae and Makemake.

What distinguishes the dwarf planets from the others is that the have failed to clear their orbits. There are thousands of objects in the Asteroid Belt and many objects in the general area of Pluto and beyond.

The question is whether Pluto and the others are planets. There's a lot of controversy over this, but here's my take on the matter ...

A few years ago, I met the actor Kenny Baker, who played (amongst other roles) R2-D2 in the Star Wars films. Kenny Baker is 3' 8" high, and so he might be referred to as a dwarf. However, he is still a human being, whatever his size. So surely if a dwarf human is still a human, then a dwarf planet is still a planet - it's just a small one. In fact, that's what the term "dwarf planet" means.

If the IAU didn't want these objects to be known as planets, they should have given them a name which didn't include that word, and come up with a term like "Hoogilyfliffs".

So, in my view, we have a total of 13 planets in our solar system:

Mercury Venus Earth Mars Ceres Jupiter Saturn Uranus Neptune Pluto Haumae Makemake and Eris

This obviously means that we need a new mnemonic, so here's my suggestion ...

My Very Excellent Mother Creates Jam Sandwiches Using Newly Purchased Hartley's Marmalade - Excellent!

There are several definitions currently in use by astronomers. There are two very popular ones. One with 8 planets, and one with 13 planets. Personally, I prefer the 13 planet definition.

Mercury, Venus, Earth, Mars, Ceres, Jupiter, Saturn, Uranus, Neptune, Pluto, Haumea, Makemake, Eris

If you're interested, a mnemonic to remember this is

My Very Elegant Mother Creates Jelly Surprise Using Nice Pink Hot Munchy Eggs

In this solar system, there are eight planets which are in existence. In order from the closest to the farthest from the sun, it goes as the following:

Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune.

The above are the eight planets of the solar system. The issue with Pluto is a rather controversial matter, Pluto is no longer a planet. They have reclassified the celestial body known as Pluto into a category which is referred to as the "Dwarf Planet" which is not a planet. The reason people did this is because a celestial body needs to follow a set criteria of rules to be considered or regarded as a planet. There are three rules and they are typed below:

1. The celestial body needs to have enough gravity to pull itself into a sphere.

2. The celestial body needs to orbit a star.

3. The celestial body needs to have enough gravitational strength to clear its orbital zone.

Pluto follows the first and second rules but as for the third, that's where the problem exists. Pluto is an extremely small planet, or rather, WAS and extremely small planet, it was the smallest planet in the solar system and now that title belongs to Mercury. Because of Pluto's relatively small mass, the previously considered planet had a weak gravitational field. There is lots of debris in the orbital paths of the planets, and the planets need to have enough gravity to either suck these rocks and other particles in or it needs to be able to throw them away from their orbital zone. Pluto cannot do this. And also, I've heard somewhere else that Pluto also crosses paths with Neptune, which is the reason why it doesn't follow the third rule and thus, is not considered a planet. This is indeed a controversial matter, for reasons that I myself cannot see, I've seen on TV people protesting for "Plutonian rights", I truly have got no idea whatsoever why it affects them if other people consider or not consider that celestial body known as Pluto to be a planet. A summarized answer to your question is eight planets which are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune. Those are the eight planets in the solar system. And if you are wondering why they had to make up this criteria and declassify Pluto, it is because there are hundreds of other celestial bodies similar to Pluto so if they had considered Pluto to be a planet, they would have to include hundreds of other rocks and planets, which is why they came up the category of the dwarf planet to fit all of those hundreds of other dwarf planets including Pluto in to it.

In order of increasing distance from the sun it is:

Mercury

Venus

Earth

Mars

Jupiter

Saturn

Uranus

Neptune

Pluto has been reclassified as a sub-planet

You forgot Saturn :

mercury, venus, earth, mars, jupiter, Saturn, uranus, neptune

Pluto is no longer considered to be a planet. It is merely one of about 1000 objects that have so far been discovered beyond Neptune.

Check out this article on Pluto :

http://en.wikipedia.org/wiki/Trans-Neptunian_objec...

It isn't really different. What has changed is the professional astronomers' rather arbitrary definition of what a planet is. As more and more objects in deep space beyond Pluto came to light, it becma e clear that there was a classification problem. If Pluto was still to be classified as a planet, it was obvious that we might end up having to recognise dozens of planets, or more. Astronomers felt this was untidy, and instead took the other route, of downgrading Pluto to a new category of 'dwarf planet', so now, from the point of view of professional astronomers, 'planet' end with Neptune. The facts, however, have not changed. Pluto is exactly what it was while you were growing up, and if you want to continue to regard Pluto as a planet, that is your good right.

(in order of distance from sun; shortest distance to longest distance)

mercury, venus, earth, mars, jupiter, saturn, uranus, neptune

hope this helps! :)

cedric

Pluto is no longer considered a major planet- it's a dwarf, because they found more ice planets like it further beyond so it's not really special anymore.

Pluto is no longer a planet. It's now considered a dwarf planet. also you forgot Saturn

Douglas, Douglas, Douglas. "I here it's wrong?" Didn't you attend school? Didn't they teach you the difference between Here and Hear?