Dwarf planets are formed in the same way as normal planets, and they orbit a host star just like our sun.

So what makes them dwarfs?

Are there any other dwarf planets like pluto?

Planets are formed when there is dust around a star left over from when that star was born.

All that dust starts to spin around the new star, colliding and clumping up.

You know, if you've ever rolled a snowball, it's kind of a similar process.

The particles become bigger and bigger, and eventually form rocks.

What happens next depends on how far they are from the host star.

In the colder regions farther out from the star, tiny fragments of ice connect to the dust, forming a planetary core, like a dirty snowball.

The process will also draw gases into the planet, making gas giants like Saturn and Jupiter.

Even farther out, ice giants like Uranus and Neptune form, but scientists don't know quite as much about how those were created.

Now, closer to the host star, it's warmer.

So rocky planets like Earth Mercury, Venus, and Mars form.

But it's not just planets formed in these systems.

Smaller dwarf planets can also exist.

These are planets that are irregularly shaped, and they haven't cleared their orbit of debris.

You've probably heard of Pluto, which used to be considered a planet, and is now thought of as a dwarf planet.

But there are actually four other dwarf planets in our solar system: Ceres, Haumea, Makemake, and Eris.

Maybe when they clean up their act, or orbits, they'll get to be planets, too.

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