What is up there in the sky? There often are some clouds, but you also often can see some objects up there: the sun, the moon and many, many stars. What are they? Many people have wondered about that. Here are some explanations:

The sun

It moves. Or maybe we move, and it is just hanging up there? It provides a lot of bright light with some heat attached to it; many people still get very painful sunburn in the summer - they know about sunburn and how dangerous it can be, but still they get it by being too long in the sunshine. Actually, after long and many studies, it was found that we move round and around the sun. Where are we? We are on a large ball that is called Earth. The sun, too, is a very large ball, much larger than the Earth; it only looks small because it is so very far away. The Earth - that's where we are - is one of the planets. All the other planets of what we call the Solar system also rotate around the sun. More about the Sun, the Solar system, and the Earth later.

The moon

It also moves. It moves around and around the Earth, just like a spaceship or a satellite. It too is getting a lot of light and heat from the Sun, and we can see the part of the moon that receives the Sun's light and heat because the moon is like some kind of mirror. Some people went there some years ago and it was on TV. More about the moon later too.

The stars

The stars, all of them more like the sun, everyone of them, are very far; if we would want to travel there it would take us many years. Many of these "stars" are really not just one, but many suns, very, very far from us, and we call them galaxies. Our sun, all the planets, all of us, are also part of a whole group with many other suns (some with planets too?), a galaxy. More about stars and galaxies later as well.


Planets can be found around many stars. They can be as small as Pluto or as large as Jupiter or anywhere in the middle. Planets come in several types. First are rocky planets like Earth and Mars. Second are the gas types like Jupiter and Saturn.

Space objects

There are many things in space that are not planets, moons, or stars. For example there are asteroids, comets, meteor, and gas clouds.



Beyond The Solar System

How Big is The Milky Way Galaxy?

What is Dark Energy and Dark Matter?

What are black holes, wormholes and white holes?

Videos of black holes and worm holes  

Extended Activities: