Stars
The color of a star you can see how hot he is. Yellow stars are around 6,000 degrees Celsius, red stars are around 3,000 degrees Celsius. Blue stars are hottest.
Because each star has a gravitational field, he draws everything that at a certain distance around it. Further away things go into orbit to orbit the star. This is when everything has a gravitational field so. Only the spheres in orbit around a star turn called planets. Globes in orbit around a planet called moons.
Our own sun is a star, a medium. It is the star that is closest to the Earth. The planetary system where we live is called the solar system.
How is a star?
Stars form from gas and dust particles from space, or rather out of nebulae. Sometimes shapes that dust and gas together a big cloud. That cloud is billions of kilometers wide and called a nebula. They consist mostly of hydrogen and helium and icy particles of space dust. The haze particles are becoming more and sometimes it lumps. A clump may be increasing. And then the clot under the influence of its own gravity will shrink. The lump is getting hotter and gradually turns into a baby star! This shrinking gas cloud also called a protostar.
Nebulae are very cold, but they therefore contain all the ingredients to form a star.
Stars give heat but how?
They split hydrogen and helium formed therefrom. In the fission heat is released.
Constellations:
A long time ago people were staring at the stars. And when they saw all figures. And those figures who gave them names: They thought of hey !, it looks like a Hunter. They knew a good hunter and named 'Orion'. And so they called the Orion constellation. Orion is one of the most beautiful constellations! And they thought hey !, it's like a big bear. That's in their language 'Ursa Major' The Great Bear is well known. You will see a saucepan, but the big bear is even greater.
If constellations put them there always drawn lines between. In total there are 88 constellations. But you can see not all at once, it depends on where you are on earth and what the time is. Then a star chart is useful. On this map you can see at what point you what part of the sky you can see.
When can you see the stars?
It has to be dark, and there must be little light of a city. For example, in the desert, there is no light from lampposts and houses. It is therefore very dark. And then you see a lot of stars.
It is also important that it is not cloudy.
It is best to look at a high place.
You can look at a star dome, but you can do even better in the mountains. In the mountains you are very high and there is little light of cities.
With the naked eye you can see a lot, but with binoculars you can see even more. And if you're a star or planet to view very well, then you better use a telescope. If you want to watch again stars with a telescope you can do that at an observatory.
Amorous stars:
The two stars in a binary are obviously not in love. But they always stay together, like a couple in love.
Moving stars?
The stars move, but compared to other stars they hardly will appear stars to stand still. The sun moves too. These moves at 230 km / s by the Milky Way, our own galaxy. This galaxy is moving again through the universe along with many other galaxies.
Habitable zone:
The habitable zone is the area between two specified distances from the star. Outside those distances are too hot or too cold and it naturally so that you'll be dying once. Optionally you at great distances from a star have a special heat source in order to survive, so that's why it is said here "naturally".
Outside the habitable area is for example 800 ° C or -150 ° C. Few planets located in the habitable zone. The only planets in our solar system that are in the habitable zone are the Earth and Mars. Hence, there are no plans for a manned space flight to Venus and Mars to be for (the two planets are the closest to the Earth).
If a planet is outside the habitable zone, you can say with all certainty that there is no finding on life.
A star at the end of his life
Stars die when the supply of nuclear fuel. First, burns the hydrogen, after that the helium. When the helium runs out, the nuclear energy disappears over quickly and then explode, shrink or cool them off. Stars burn a few million to many billions of years. The smallest stars but little fuel, but they eventually do it very sparingly and live longer than the big stars. A small star has enough gas to 10 billion years stay on.
When a star like our own Sun has no hydrogen in the core more, it becomes a red giant. In our own sun will occur over approximately 5 billion years. A star that is much larger and heavier than our sun turns into a supernova
