Ceres is is the smallest of the five dwarf planets currently recognised. Its equatorial diameter is 974.6km and it is orbit around our sun between the orbits of Mars and Jupiter.

It is said that it looks similar to Pluto, though being as far away from the Sun as it is, it's atmosphere freezes over and gleams brightly reflecting the sunlight changing its image temporally.

Sedna is not a planet, according to the International Astronomical Union (IAU). Because Sedna is so distant and so small, it has not yet been classified, but is probably a Trans-Neptunian Object. It may or may not turn out to meet the standards of a "dwarf planet", depending on whether its mass is high enough to force it into a roughly spherical shape.

Sedna's orbit is highly elliptical and has not been completely analyzed, but its perihelion appears to be 76 AU with an aphelion of 975 AU. This would give it an orbital period of perhaps 12 thousand years.

Mercury is the smallest of the major planets, but it won't be classified as a dwarf. The reason that it won't be classified as a dwarf planet is that it has cleared its orbit of other objects. Pluto, Ceres, Eris, and the other dwarf planets all have a bunch of other junk in their orbits, and that is why they aren't considered planets any more.

No. It is considered as a dwarf planet If you order a small Pepsi, you still get Pepsi, right? Pluto is a planet. It is a special class of planet; it is a dwarf planet. What it is not is a major planet.

The planets orbits are the routes or paths that the planets follow around our sun. One orbit is one trip around the sun (one year).

Pluto is the smallest of all known Planets. Now it is considered to be a "dwarf planet". It takes 248 years to make one orbit around the sun.

As to where it is, depends on time. Earth and Pluto move in different orbits, so to detect where Pluto is, requires an exact time.

Due its distance, it is not known for sure if Sedna does have an atmosphere. Scientists have speculated that a tenuous atmosphere may exist for some of its orbit, from the Nitrogen that is present.

ice water.

URANUS

Generally it's the size. If an asteroid were to be big enough to achieve hydrostatic equilibrium (approximately spherical in shape), then it may be classed as a dwarf planet, such as Ceres. Asteroids are generally too small to active this shape under their gravity so are not classed as dwarf planets.

Mercury, because it is the smallest planet in our solar system

Eris is a dwarf planet, because it is sufficiently massive that it's formed into a spheroid due to its own gravity, but it has not cleared its orbital path, as it would need to in order to be considered a planet.

Eris is the largest known object in the Kuiper Belt.

Eris is the largest dwarf planet, about 25% larger than Pluto.

Pluto was discovered in 1930 and originally called a planet. In 2006, Pluto was re-classified to be a dwarf planet due to the discovery of a number of similar rocky, icy bodies in the solar system. To avoid increasing the number of planets dramatically, Pluto and similar bodies were re-classified.

Here in our own solar system, the four inner planets are rocky; Mercury, Venus, Earth and Mars.

Beyond our solar system, we've detected over a thousand planets, but we're unable to discover any details about the surface. As far away as they are, I'm still amazed that we can discover that they exist!

to

Astronomers have a specific definition of what separates a planet from a comet from a dwarf planet. The main thing I heard about Pluto is that it and its moon, Charon, orbit each other. One does not orbit the other. It's complicated and doesn't really matter.

they believe our solar system was formed by the big bang

A metiorite. I believe what you're talking about is a meteoroid, not an asteroid. An asteroid is rather large, revolves around the sun, and when one hits the Earth, and a few have, it is disastrous. A meteoroid, on the other hand, is much smaller and when it hits the Earth's atmosphere and burns up (due to the friction of the atmosphere) it is called a meteor. After it reaches the Earth's surface, it is called a meteorite. http://dictionary.infoplease.com/meteor merci, have a good day.

Mercury has a diameter of 2,439.7 km

Pluto has a diameter of 2,306

So that means that Mercury is a little bigger