THE COOL AND CURIOUS WORLD OF DWARF PLANETS - TINY PLANETS WITH BIG MYSTERIES

You’ve probably heard of the big planets like Jupiter, Mars, and Earth—but did you know there are smaller, mysterious worlds out there called dwarf planets? They may be little, but they’re full of surprises, icy mountains, and even possible underground oceans!  

Let’s venture through our solar system and meet these tiny wonders. 

Photo credit: NASA Science

WHAT IS A DWARF PLANET?

A dwarf planet is kind of like a regular planet, but with a few important differences. To be a dwarf planet, an object must: 

• Orbit the Sun 

• Be round, or almost round, in shape 

• Not have cleared away other space rocks near its orbit 

• Cannot be a moon 

  
  

In 2006, scientists made a big decision. They decided that Pluto didn’t fit all the rules for a regular planet and gave it a new title: dwarf planet. And Pluto isn’t alone—there are more out there just like it. 

PLUTO: THE MOST FAMOUS DWARF PLANET

Pluto used to be called the ninth planet, but now it's the most famous dwarf planet in space. It lives far from Earth in a place called the Kuiper Belt, which is full of icy objects. Pluto has five moons, and its biggest one is called Charon. 

In 2015, a spacecraft named New Horizons flew by Pluto and showed us just how AMAZING it is. Scientists saw icy plains, tall mountains made of frozen water, and even signs that there might be an ocean beneath the surface!  

ERIS: PLUTO'S SPACE RIVAL 

Eris is another icy dwarf planet that’s almost the same size as Pluto, but heavier. It also lives far away in a cold area of space. Eris has one moon named Dysnomia. Its bright, shiny surface might be covered in ice, and just like Pluto, it might have a secret ocean underneath!  

HAUMEA AND MAKEMAKE: THE UNUSUAL PAIR  

Haumea and Makemake are two more dwarf planets in the Kuiper Belt. Haumea is shaped like an egg because it spins really fast. It even has a ring around it and two moons. Makemake has a reddish color because of something called tholins, which are special materials made by sunlight hitting its surface. Makemake also has one moon that was discovered in 2016. 

CERES: THE DWARF PLANET CLOSE TO HOME  

Ceres is the closest dwarf planet to Earth. It lives in the asteroid belt between Mars and Jupiter. It’s not made of ice like the others—it’s made of rock and water. In 2015, NASA’s Dawn spacecraft visited Ceres and discovered bright spots inside its craters. These spots are made of salt left behind when water from below the surface dried up. 

Scientists think Ceres might still have liquid water hidden underground, which means it could be one of the best places to search for signs of life!  

WHY DWARF PLANETS MATTER  

Dwarf planets help us understand how the solar system formed. They are like time capsules, holding clues from billions of years ago. Even though they are small, they teach us big lessons about space. 

Some dwarf planets are active, with changes happening on their surfaces. That means exciting things can happen even on the smallest worlds. Scientists are still learning from these faraway places and are planning future missions to explore more of them. 

Dwarf planets might be small, but they’re some of the most interesting places in the entire solar system. Who knows what secrets they’ll reveal next? 

Now that you’ve learned all about dwarf planets, take our quiz and see how much you remember! Be sure to check out our Learn with Flight blog for other fun space and aviation themed articles. When you take the quiz, you’ll earn points that can be redeemed at your local Flight Adventure Park—perfect for scoring Flight merchandise and jump time! And if you are feeling inspired, plan a visit to our space-themed adventure park. You can jump, explore, and imagine your own space adventure—right here on Earth! 

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