Read about planets, stars, galaxies and the people and tools used to explore space. Choose an article below; its reading controls let you move between the available levels.
1,134 public articles · Page 2 of 24
The sky looks like a big ball. Everything in space seems to be on it. It helps us find stars. We use it to see where things are. It is a neat tool. Do you like looking at the stars?
Early Reader · Change the reading level on the articleThere is a big group of stars. It is called Centaurus A. It has a dark line of dust. This dust helps new stars grow. It is very bright in the sky. Can you look for it?
Early Reader · Change the reading level on the articleSome stars change their light. They grow big and small. They also get bright and dim. This helps us find how far they are. We can see them far away. Do you like looking at stars?
Early Reader · Change the reading level on the articleCeres is a small world in space. It lives between Mars and Jupiter. It is made of rock and ice. This world is very hard to see. It is a special dwarf planet. Do you want to see more space?
Early Reader · Change the reading level on the articleA group in China looks at space. They study the moon and stars. They send things up to the sky. This helps us learn about space. It is very cool. Do you like the stars?
Early Reader · Change the reading level on the articleThe world started long ago. It was very hot and small. Then it grew and grew. It grew into big stars and galaxies. Now we live in it. Do you like to look at the stars?
Early Reader · Change the reading level on the articleSpace is very big. We use a ladder to find distances. We start with things that are close. Then we use them to find far things. This helps us know how big space is. Can you look at the stars?
Early Reader · Change the reading level on the articleA soft glow fills all of space. It comes from a long time ago. This glow helps us learn about the start of everything. It is everywhere we look. Can you imagine a glow in the dark?
Early Reader · Change the reading level on the articleTiny bits fly through space. They come from far away. They move very fast. They hit the air around Earth. This makes a big splash. They are all around us. Can you feel them?
Early Reader · Change the reading level on the articleSpace is getting bigger. It is growing very fast. A hidden force helps it grow. This force is in empty space. It helps the whole universe move. Do you like looking at the stars?
Early Reader · Change the reading level on the articleA big star once exploded. This left a bright cloud. It looks like a crab. It is far away in space. We need tools to see it. Can you find it in the sky?
Early Reader · Change the reading level on the articleA long time ago, there was a big city. It sat by a large river. Kings lived in a grand palace there. It was a very busy place. Many people lived there together. Now, we can see its old ruins. Do you like old cities?
Early Reader · Change the reading level on the articleThere is a dark spot in space. It is a black hole. It stays near a big blue star. The star sends gas to the hole. This makes a bright light. Can you find it in the sky?
Early Reader · Change the reading level on the articleThe universe is getting bigger. It is growing very fast. A hidden force helps it grow. This force is everywhere in space. It is a big mystery to us. We are still learning about it. Do you want to look at the stars?
Early Reader · Change the reading level on the articleSpace has a big secret. Most of it is hidden. We cannot see it. It does not use light. But it pulls on things. It helps stars stay in place. Can you find it?
Early Reader · Change the reading level on the articleSome clouds in space are very dark. They hide the stars behind them. Tiny bits of dust make them look black. These clouds can even help make new stars. They look like dark spots in the sky. Can you find a dark spot…
Early Reader · Change the reading level on the articleA man named Copernicus had a big idea. He said the Sun is in the middle. The Earth moves around the Sun. This helps us see the stars. It is a great discovery. Do you like looking at the sky?
Early Reader · Change the reading level on the articleA dwarf galaxy is a small group of stars. They are much smaller than our own home. Some are very dim and hard to see. They can move around big galaxies. These tiny groups help us learn about space. Can you find a…
Early Reader · Change the reading level on the articleSome worlds are very small. They go around the Sun. They are round like a ball. They are not big planets. They are called dwarf planets. Pluto is one of them. Do you like space?
Early Reader · Change the reading level on the articleThere is a big cloud in space. It looks like a bird. New stars grow inside it. This helps the sky stay bright. It is a beautiful sight. Can you see it in the sky?
Early Reader · Change the reading level on the articleAn eclipse is a shadow in space. One object moves in front of another. This blocks the light. It can look like the Sun or Moon is hiding. It is a very cool thing to see. Have you seen a shadow before?
Early Reader · Change the reading level on the articleThe Sun follows a path in the sky. This path is called the ecliptic. It takes one year to finish. We see the Sun move along it. This helps us know the time of year. Do you like looking at the stars?
Early Reader · Change the reading level on the articleEdmond Halley was a man who loved stars. He studied the sky and the sea. He even found a comet in space. That comet has his name now. He was very smart. Do you like to look at the stars?
Early Reader · Change the reading level on the articleEdwin Hubble looked at the stars. He found many far away groups of stars. These are called galaxies. He saw that the whole sky is growing. This helps us know our world. Do you like to look at the stars?
Early Reader · Change the reading level on the articleSome galaxies look like round balls. They are made of old stars. These stars are red. They do not make many new stars. They are very big and bright. Can you find them in the sky?
Early Reader · Change the reading level on the articleEnceladus is a moon of Saturn. It is covered in white snow. It is very cold there. Big jets of water spray from the moon. This helps make Saturn's rings. It is a very cool place! Do you like snow?
Early Reader · Change the reading level on the articleWe use maps for the sky. These maps help us find stars. They show where a star sits. This helps us use big telescopes. It is fun to look up! Can you find a star tonight?
Early Reader · Change the reading level on the articleThe sun is right over the middle of Earth. This happens twice every year. Day and night are about the same length. This helps us know the seasons are changing. It is a special time. Can you see the sun rise in the east?
Early Reader · Change the reading level on the articleEris is a big world far away. It stays in the dark, cold space. It has a small moon too. This world is very heavy. It helps us learn about space. Do you like to look at the stars?
Early Reader · Change the reading level on the articleEuropa is a moon. It orbits a big planet. The moon is made of ice. It has a big ocean under the ice. This ocean might have life. Could you swim in that water?
Early Reader · Change the reading level on the articleMany countries work together for space. They build big rockets. They send tools to the Moon. They even look at the Sun. This helps us learn about the stars. Do you like space?
Early Reader · Change the reading level on the articleSome places in space are very dark. They have a special line. Light cannot get past this line. It stays stuck inside. This helps us learn about space. Can you find a dark spot in the sky?
Early Reader · Change the reading level on the articleSome planets live far away. They orbit other stars. These are not our stars. They can be big or small. We look for them in space. Do you like stars?
Early Reader · Change the reading level on the articleWe send robots to Mars. These robots travel far away. They look at red rocks and dust. This helps us learn about space. It is a big job! Do you want to go to Mars?
Early Reader · Change the reading level on the articleSpace has lots of dust. This dust can hide stars. It can even change their color. It makes stars look red. This happens because the dust blocks blue light. Can you see the stars tonight?
Early Reader · Change the reading level on the articleCould life live far away? Some people think so. They look at the stars. They wonder if we are not alone. Maybe other worlds have life too. It would be a big find! Do you think we will find them?
Early Reader · Change the reading level on the articleOur Sun and planets formed long ago. A big cloud of dust spun around. Most of the stuff made the Sun. The rest made the planets. This is our home in space. Do you like looking at the stars?
Early Reader · Change the reading level on the articleOur galaxy has a middle. It is a very bright place. A big black hole lives there. It helps hold the stars. It is a busy spot in space. Do you like to look at stars?
Early Reader · Change the reading level on the articleHuge groups of stars are called galaxies. Some look like flat disks. Others look like round balls. They can change over a long time. They can even bump into each other. Do you like looking at the stars?
Early Reader · Change the reading level on the articleMany galaxies live together in space. They form big groups. Some groups are very large. These are called clusters. They stay together in a big bunch. We live in a group too! Can you look up at the stars?
Early Reader · Change the reading level on the articleSpace has many big groups of stars. We call these groups galaxies. Some look like round balls. Some look like spinning wheels. We can group them by how they look. It helps us learn about space. Do you like looking at…
Early Reader · Change the reading level on the articleBig stars can go boom. These are huge explosions. They happen far away in space. They are very bright. They are the brightest things in the sky. Can you see the stars?
Early Reader · Change the reading level on the articleGanymede is a very big moon. It goes around Jupiter. It is bigger than the planet Mercury. It has a lot of water inside. This water is under the ice. It is a giant world. Do you want to visit it?
Early Reader · Change the reading level on the articleGeorges was a smart man. He studied the stars. He found out that space grows. This helps us know our world. It is very cool! Do you like looking at the stars?
Early Reader · Change the reading level on the articleSome tools fly high in space. They stay over one spot. They move with our world. This helps us watch the weather. It also helps us talk to friends. Can you see them in the sky?
Early Reader · Change the reading level on the articleSome space tools stay in one spot. They spin around the Earth. They move at the same speed as our world. This helps us talk to people far away. It makes things easy for you. Can you see them in the sky?
Early Reader · Change the reading level on the articleSome planets are very big. They are much larger than Earth. They do not have a hard floor to stand on. They are made of gas and ice. These big worlds are amazing. Can you name one?
Early Reader · Change the reading level on the articleSome stars are very big. They are much larger than our Sun. These stars are very bright. They shine a lot in the sky. We can see them far away. Do you like to look at stars?
Early Reader · Change the reading level on the article