Blast off into the universe! Learn about planets, stars, black holes, and everything in between — made just for curious kids like you!
Pick your grade and discover space topics made just for you!
The Sun, Moon, and stars! Learn why the Moon changes shape and what makes day and night.
Earth is our home planet! Learn what makes Earth special and how it travels around the Sun.
There are 8 planets in our Solar System! Learn their names and how far they are from the Sun.
Stars come in different sizes and colors! Some are tiny white dwarfs, some are massive red supergiants.
The universe is full of galaxies! Our Milky Way galaxy is just one of trillions out there.
Humans have explored space since 1957! Learn about rockets, the ISS, and living in orbit.
Dig into gravity, black holes, and what lies beyond. Is there life on other planets? Let's find out!
Welcome, tiny explorer! 🌈 Let's discover the Sun, Moon, and stars together. Find out why the sky changes from day to night and watch how the Moon grows and shrinks each night!
The Sun is a giant glowing ball of hot gas! It gives us light and warmth every single day. Without the Sun, Earth would be cold and dark — no plants, no animals, no us!
The Moon orbits Earth and we see different amounts of its sunlit side each night. That's why it looks like a sliver, a half circle, or a full glowing ball — it's always the same Moon!
Stars are far-away suns! They look tiny because they are super far away. On a clear night you can see thousands of them twinkling in the sky. Our Sun is actually a star too!
Earth spins like a top! When your side faces the Sun, it's daytime and bright. When your side faces away from the Sun, it gets dark — that's nighttime! Earth spins all the way around every 24 hours.
The Sun is so big, 1 million Earths could fit inside it!
The Moon is 384,400 km away — but you can see it with just your eyes!
There are more stars in space than grains of sand on all Earth's beaches!
Earth spins so fast its surface moves at 1,670 km per hour — but we can't feel it!
Draw the Moon every night for a week! Watch how it changes shape from a thin crescent to a full moon circle.
Sort picture cards into "daytime" and "nighttime" piles. What do you see in the day sky? What do you see at night?
On a clear night, go outside with a grown-up and try to count the stars in one small patch of sky. How many can you find?
Use a flashlight as the Sun and a ball as Earth. Spin the ball slowly — one side gets light (day) and the other gets dark (night)!
Earth is your home — and it's an amazing planet! 🌿 Learn how our planet travels around the Sun, what causes the seasons to change, and why sunsets are so colorful!
Earth is a planet — a huge, round world floating in space! It's covered in oceans, land, air, and teeming with life. Earth is the only planet we know for sure has living things on it.
Earth travels around the Sun in a big oval path called an orbit. One full trip takes 365 days — that's one year! This journey around the Sun is what gives us our seasons.
Because Earth is tilted as it orbits the Sun, different parts get more sunlight at different times. That's why we have spring, summer, autumn, and winter — and why they happen at opposite times north and south!
The Sun appears to rise in the east and set in the west every day because Earth is spinning! Sunsets turn orange and pink because sunlight travels through more atmosphere, scattering the colors.
About 71% of Earth's surface is covered in water — we live on a water world!
Earth is the densest planet in the solar system — it's very compact and heavy!
Earth has an invisible magnetic field that protects us from harmful solar radiation!
Earth is in the "Goldilocks Zone" — not too hot, not too cold, just right for life!
Place a lamp in the middle of a room as the "Sun." Walk in a big circle around it — you're orbiting just like Earth! Notice how some spots feel warmer (closer to the lamp).
Draw the same tree four times — spring blossoms, summer leaves, autumn colors, winter bare. Label each season and explain why the tree changes!
Watch a sunset with a grown-up. What colors do you see? Orange, pink, purple? Draw what you see and describe why the sky changes colors as the sun goes down.
Record the weather every day for two weeks. Is it sunny, cloudy, rainy, or windy? At the end, count which weather happened most!
There are 8 amazing planets orbiting our Sun — and each one is totally different! 🌌 Learn their names and order, meet their moons, and find out which planet could float in a bathtub!
The Sun is the center of our solar system — a massive star so big that all 8 planets, their moons, asteroids, and comets all orbit around it. Its gravity holds the whole solar system together!
In order from the Sun: Mercury, Venus, Earth, Mars (the rocky planets), then Jupiter, Saturn, Uranus, Neptune (the giant planets). A helpful trick: My Very Eager Mother Just Served Us Nachos!
Moons are natural satellites that orbit planets. Earth has 1 Moon. Mars has 2 tiny moons. But Jupiter has 95 moons and Saturn has 146! Some moons are bigger than the planet Mercury.
Each planet travels in an oval orbit around the Sun. Closer planets orbit faster — Mercury zooms around in just 88 days! Neptune is so far away it takes 165 years to make one full orbit.
Saturn is less dense than water — it would actually float if you had an ocean big enough!
Mars has the tallest volcano in the solar system — Olympus Mons is 3× taller than Everest!
Jupiter is so big that 1,300 Earths could fit inside it!
Uranus rolls on its side as it orbits — scientists think it was knocked over by a giant impact!
Play the Planet Order game on AstroVoyager — drag the planets into the correct order from the Sun! Can you do it without any hints?
Draw and cut out all 8 planets, size them roughly correctly (Jupiter huge, Mercury tiny!). Hang them in order from a coat hanger to make a solar system mobile!
Use different sized balls to represent planets — a basketball for Jupiter, a pea for Mercury! Walk the right distances apart in a field to feel how big our solar system really is.
Make up your own silly sentence where each word starts with a planet's first letter: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune. What's your sentence?
Stars are not all the same! 🌟 Some are tiny and cool, some are gigantic and blazing hot. Learn to spot constellations, discover our home galaxy, and find out what happens when a star explodes!
Stars come in many sizes and colors. Red stars are coolest, yellow (like our Sun) are medium, and blue-white stars are the hottest! Our Sun is a medium-sized yellow dwarf star — perfectly ordinary, which is lucky for us!
Ancient people connected the dots between stars and imagined pictures — animals, heroes, objects. These patterns are called constellations. There are 88 official constellations. Orion, Big Dipper, and Cassiopeia are some of the most famous!
All the stars we see in the night sky are part of our galaxy — the Milky Way. It contains 100–400 billion stars! Our solar system sits in one of the spiral arms. On a very dark night, you can see the Milky Way as a faint band of light.
When a massive star runs out of fuel, it explodes in a gigantic blast called a supernova! For a brief time, it can shine brighter than an entire galaxy. The explosion scatters elements like iron and carbon into space — elements that eventually make planets and even us!
The red supergiant star Betelgeuse in Orion is 700 times wider than our Sun!
The Milky Way is 100,000 light-years across — light takes 100,000 years to cross it!
After a supernova, the leftover core becomes a super-dense neutron star — the size of a city but heavier than the Sun!
Stars twinkle because their light passes through moving layers of Earth's atmosphere!
Play the Constellation game on AstroVoyager! Click stars in the right order to draw the Big Dipper, Orion, and Cassiopeia — just like ancient astronomers did!
Poke tiny holes in black paper with a pin to match a constellation pattern. Shine a flashlight through from behind in a dark room — you've made your own star viewer!
Pick one constellation and research its mythology story. Who or what does it represent? Draw the constellation and write or tell its story to your class.
Use dark blue/black paper and white, yellow, and purple paint to create your own galaxy! Swirl the paint to make spiral arms and add hundreds of tiny star dots.
The universe is HUGE — and full of weird and wonderful things! ☄️ Explore the galaxies beyond our Milky Way, track comets and asteroids, and discover the incredible telescopes that let us see billions of light-years away.
A galaxy is a massive system of billions of stars, gas, and dust all held together by gravity. There are trillions of galaxies in the observable universe! The nearest large galaxy to ours is the Andromeda Galaxy — it's on a collision course with the Milky Way... in about 4 billion years!
Comets are balls of ice and rock that orbit the Sun. When they come close to the Sun, they warm up and release gas and dust, creating a glowing tail that always points away from the Sun. Halley's Comet visits our inner solar system every 75 years!
Asteroids are rocky objects orbiting the Sun — leftover building blocks from when the solar system formed 4.6 billion years ago. Most are in the Asteroid Belt between Mars and Jupiter. They range from pebble-sized to hundreds of kilometers wide!
Telescopes gather light to make distant objects appear closer and brighter. The Hubble Space Telescope has taken some of the most incredible images of space. The new James Webb Space Telescope can see galaxies that formed just 300 million years after the Big Bang!
There are more galaxies in the universe than grains of sand on Earth — over 2 trillion!
A comet's tail can be hundreds of millions of km long — always pointing away from the Sun!
The James Webb Space Telescope sees 13.5 billion light-years away — almost to the beginning of the universe!
The asteroid that wiped out the dinosaurs was 10–15 km wide — about the size of a city!
Look up three famous telescopes: Hubble, James Webb, and a ground telescope like the Very Large Array. How do they work? What have they discovered? Make a poster comparing them!
Make a comet using a ball of crumpled foil for the nucleus, and streamers of white and blue tissue paper for the tail. Hold it up — which direction does the tail point when facing a lamp (the Sun)?
Search for these words in the AstroVoyager Glossary: comet, asteroid, galaxy, nebula, light-year. Write each definition in your own words and draw a picture for each one!
Drop different sized rocks into a tray of flour or sand from different heights. Compare the craters! Larger objects and higher drops make bigger, deeper craters — just like asteroid impacts!
Humans have ventured beyond Earth — and it's harder than it looks! 🛸 Discover how rockets work, what life is like on the International Space Station, and explore the history of the most daring missions ever attempted!
Rockets use Newton's Third Law: every action has an equal and opposite reaction. By blasting gas downward at enormous speed, the rocket is pushed upward with equal force. To reach orbit, a rocket must travel faster than 28,000 km/h — that's 25 times faster than a commercial plane!
In microgravity on the ISS, everything floats! Astronauts eat food from pouches, sleep in bags strapped to walls, and exercise 2 hours every day to keep their muscles from weakening. They orbit Earth every 90 minutes — seeing 16 sunrises every day!
Unmanned spacecraft called probes are sent to explore places too far or hostile for humans. Voyager 1 has been flying for over 45 years and is now in interstellar space — farther than any human-made object ever! The Perseverance rover is exploring Mars right now.
On July 20, 1969, Neil Armstrong and Buzz Aldrin became the first humans to walk on the Moon! The Apollo program landed 12 people on the Moon between 1969 and 1972. NASA's Artemis program is planning to return humans to the Moon, including the first woman and person of color!
SpaceX's Starship is the largest rocket ever built — taller than the Statue of Liberty!
Voyager 1 is now over 23 billion km from Earth — and its signal still reaches us!
Astronaut footprints on the Moon will last millions of years — there's no wind to erase them!
Rocket re-entry heats the spacecraft to 1,650°C — hotter than a lava flow!
Thread a straw onto a string stretched across the room. Blow up a balloon, pinch it, and tape it to the straw. Let go! The air escaping pushes the balloon forward — that's rocket propulsion!
Plan a space mission to any planet or moon! Choose your destination, describe what you want to find out, draw your spacecraft, and explain what your astronauts will need to survive there.
Research a real astronaut — Yuri Gagarin, Sally Ride, Neil Armstrong, Mae Jemison, or Chris Hadfield. Write a biography about their journey and what they achieved in space!
The ISS orbits Earth every 92 minutes. How many orbits does it complete in one day? One week? One year? (Hint: divide minutes in a day by 92!) What's the total distance traveled?
You're ready for the deepest mysteries of the universe! ⚡ Explore the terrifying power of black holes, the invisible force of gravity, worlds orbiting distant stars, and the biggest question of all — are we alone?
A black hole forms when a massive star collapses under its own gravity at the end of its life. The gravity becomes so strong that nothing — not even light — can escape once it crosses the "event horizon." Time itself slows down near a black hole! In 2019, astronomers took the first-ever photograph of a black hole's shadow.
Gravity is the force of attraction between objects with mass. The more mass, the stronger the gravity. It's what keeps Earth orbiting the Sun, the Moon orbiting Earth, and keeps you on the ground. Einstein showed us that massive objects actually warp the fabric of space and time — gravity is literally a bend in spacetime!
Exoplanets are planets that orbit stars other than our Sun. Thousands have been discovered! Some are in the "habitable zone" — the right distance from their star for liquid water. The Kepler and TESS space telescopes have found thousands of worlds that might potentially support life.
Astrobiology is the science of looking for life in the universe. Scientists search for liquid water, the right chemistry, and radio signals from other civilizations. Jupiter's moon Europa and Saturn's moon Enceladus have liquid water oceans under their icy crusts — they might just harbor microbial life!
The black hole at the center of our galaxy, Sagittarius A*, is 4 million times the mass of our Sun!
Over 5,700 exoplanets have been confirmed — and we've only searched a tiny fraction of the Milky Way!
If you fell into a black hole feet-first, gravity would stretch you into a spaghetti-like strand — physicists call it "spaghettification"!
Europa's ocean contains twice as much liquid water as all of Earth's oceans combined!
Stretch a piece of spandex fabric tightly over a bowl. Place a heavy ball in the center — see how it makes a dip? Now roll a smaller ball near it — it curves toward the heavy one! This models how gravity warps spacetime.
Debate both sides: "Intelligent life exists elsewhere in the universe" vs "We are alone." Use evidence — the number of stars, habitable planets, the age of the universe — to support your argument!
Look up NASA's Exoplanet Archive online. Find an exoplanet that's in a habitable zone around its star. What is it called? How big is it? How far away? Could humans ever visit it?
Based on the conditions of Europa (cold, dark, ocean under ice), or a desert exoplanet, design what a living creature there might look like. What would it eat? How would it move? How would it survive?
Click any planet to learn more amazing facts!
👆 Tap a planet card to open its full profile!
Did you know these amazing things about the universe?
About 1,300,000 Earths could fit inside the Sun! If the Sun was the size of a basketball, Earth would be tiny as a pea.
The footprints left by Apollo astronauts in 1969 are still there! There's no wind on the Moon to blow them away.
You can't hear anything in space because there's no air! Sound needs air to travel, so explosions make zero noise.
Without gravity squishing you down, your spine stretches out. Astronauts can grow up to 5 cm taller in space!
In space, water doesn't pour — it floats in perfect round blobs! Astronauts drink by catching floating water balls.
A black hole has so much gravity nothing can escape — not even light! Time would slow down if you fell into one.
There are over 2 trillion galaxies in the universe — more galaxies than there are people on Earth!
The atoms in your body were made inside ancient stars that exploded billions of years ago. You are literally stardust!
Space is mostly -270°C (almost as cold as possible!), but in direct sunlight near Earth it can reach +120°C.
Test what you've learned! Can you get all the stars?
Play and learn at the same time!
Drag the planets from the left into the correct order from the Sun outward on the right! Mercury is closest, Neptune is farthest.
Click the stars in order (1 → 2 → 3...) to draw the constellation! Pick a constellation below to start.
Look up any space word! Search or scroll to explore.
Answer 6 questions to discover which planet matches your personality!
Resources, lesson ideas, and standards alignment for every grade level.
Sun, Moon, star, daytime, nighttime, sky, bright, dark, shine
Planet, orbit, season, Earth, gravity, rotation, hemisphere
Solar system, Mercury, Venus, Mars, Jupiter, Saturn, Uranus, Neptune, asteroid, moon
Star, constellation, galaxy, Milky Way, light-year, dwarf star, supergiant, nebula
Galaxy, comet, asteroid, meteor, telescope, universe, light spectrum, orbit
Rocket, thrust, orbit, ISS, astronaut, satellite, launch, gravity, weightlessness
Gravity, black hole, event horizon, exoplanet, atmosphere, astrobiology, dark matter
AstroVoyager supports standards including K-ESS2-1 (weather patterns), 1-ESS1-1 & 1-ESS1-2 (sun/moon/stars observations), ESS1-1 through ESS1-3 (Earth's place in the universe for Grades 2–5), and 5-ESS1-1 & 5-ESS1-2 (stars and solar system). The site's interactive glossary, quiz, and games provide formative assessment opportunities aligned to these standards.