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Mercury
The smallest planet and the closest to the Sun. It has a rocky surface and almost no atmosphere.
Blast off on a learning mission! Explore our Solar System, compare planets, discover the Moon and stars, and test your space knowledge with interactive challenges and printable activities.
Our Solar System has one star—the Sun—and eight planets that travel around it. The planets are different sizes, temperatures, and distances from the Sun.
The smallest planet and the closest to the Sun. It has a rocky surface and almost no atmosphere.
Covered by thick clouds. Its powerful greenhouse effect makes it the hottest planet.
Our home, with abundant liquid water on the surface and life as we know it.
The red planet, coloured by iron-rich dust. Scientists study it for clues about its past.
The largest planet. It is a gas giant with enormous storms, including the Great Red Spot.
Famous for its bright rings, made mostly of pieces of ice and rock.
An ice giant that rotates on a dramatically tilted axis. It looks blue-green because of methane in its atmosphere.
A distant, cold ice giant with very fast winds in its atmosphere.
Pluto is classified as a dwarf planet. Planet illustrations here are decorative and not drawn to scale.
Space is full of objects, forces, and mysteries. Start with these big ideas.
The Sun is a huge ball of hot gas that releases energy. Its light and heat make life on Earth possible.
The Moon does not make its own visible light. We see sunlight reflecting from the Moon’s surface.
The Milky Way is a galaxy containing our Solar System and billions of other stars.
Artificial satellites can help with communication, weather forecasting, navigation, and scientific research.
Astronauts learn science, teamwork, safety, and how to work in conditions that differ from Earth.
Asteroids are rocky or metallic objects. Comets contain ice, dust, and rocky material and can develop glowing tails near the Sun.
The Moon travels around Earth. As its position changes, we see different amounts of its sunlit half. These appearances are called phases.
The side lit by the Sun mostly faces away from Earth, so the Moon can be hard to see.
About half of the visible lunar disc appears lit. The Moon is about a quarter of the way through its cycle.
Earth sees nearly all of the Moon’s sunlit side, making it look round and bright.
The Moon’s phases are not caused by Earth’s shadow. Earth’s shadow causes a lunar eclipse when the alignment is right.
Complete ten questions. Read the feedback after every answer, then use your score to decide what to explore again.
Which planet is our home?
Read the clues and choose the planet you think they describe. Try the next mystery when you are ready.
I am the largest planet. I have a famous giant storm.
Change the mystery, then choose a planet and check your guess.
Generate a print-friendly activity sheet. Use your browser’s print dialog to print it or save it as a PDF.
Write the planets in order and record one fact about each.
Observe the Moon on different nights and draw what you see.
Invent a mission, choose its destination, and explain what it will investigate.
Worksheets are generated in your browser. If a worksheet does not open, allow pop-ups for your site.
Use the page as a starting point for reading, drawing, discussion, and observation.
Ask children to explain why the Moon has phases or compare a rocky planet with a gas giant using their own words.
Draw or model the planets with craft materials. Explain that the real planets differ greatly in size and distance.
Look for the Moon after sunset with an adult, record its appearance, and compare observations over several days. Never look directly at the Sun.
There are eight recognised planets: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune. Pluto is classified as a dwarf planet.
Venus has a very thick atmosphere that traps heat through an intense greenhouse effect. Mercury is closer to the Sun but has almost no atmosphere to retain heat.
Yes. The quiz and planet detective activity run on this page, and the worksheet buttons create print-friendly pages in your browser.
It is designed for children roughly ages 5–12. Younger children may enjoy the illustrations and planet names with an adult’s help; older children can explore the explanations and write their own mission plans.