The Little Worlds

Key facts

Ceres

Ceres is the biggest object in the asteroid belt and the only dwarf planet in the inner Solar System. It contains lots of water ice, and bright salty patches show that briny water once reached its surface.

Pluto

Pluto is a small icy world in the Kuiper Belt, a zone of frozen objects beyond Neptune. It has mountains of water ice, glaciers of frozen nitrogen, a thin blue atmosphere, and a giant heart-shaped plain.

Haumea

Haumea is one of the fastest-spinning large objects in the Solar System, completing a full turn in about 4 hours. All that spinning has stretched it into an egg shape. It is covered in crystalline water ice and has its own ring.

Makemake

Makemake is a reddish-brown dwarf planet in the Kuiper Belt, covered in frozen methane and ethane. It is one of the brightest objects out there, but still far too faint to see without a big telescope.

Eris

Eris is almost the same size as Pluto but more massive. It is currently about three times further away than Pluto, on a long, tilted orbit. Its discovery started the great debate about what a planet is.

Quiz

1. Who suggested the name “Pluto”?

   • ☐ Clyde Tombaugh
   • ☐ An 11-year-old girl
   • ☐ NASA
   • ☐ A newspaper

2. Which discovery led to Pluto being re-classified as a dwarf planet?

   • ☐ Ceres
   • ☐ Eris
   • ☐ Haumea
   • ☐ Charon

3. Why is Haumea shaped like an egg?

   • ☐ It was hit by a comet
   • ☐ It spins very fast
   • ☐ It is made of jelly
   • ☐ It is two objects stuck together

Find it in the sky

Use the Sky Finder at seethestar.com. Tick what you find and write when you saw it.