in our galaxy, and indeed in the whole universe, is located a great number of various celestial objects.In the night sky, we can see them as a huge amount of flickering dots and specks surrounding us from all sides.But what the celestial body called the stars and why we see them glow?
What is a star?
Star - this is a very remote, bright and hot giant mass, consisting mainly of hydrogen and helium gases.Due generated enormous pressure inside the star nuclei of hydrogen atoms begin to collide with each other, triggering a process called nuclear fusion.This celestial bodies - stars - emit an incredible amount of light, heat and energy.
main element of the stars is hydrogen.Typically, it is in it three times more than helium.The amount of helium depends on the size and age of the object: what it is, the older star.All other elements account for only 2%, but they also help scientists to accurately determine the composition, luminosity, temperature, color, size light as well as how far the star can be removed from the Earth.
What color and size can be stars?
Yes, the stars come in a variety of colors.Among them are red, orange, yellow and blue.Astronomers color can tell a lot, and it depends on the composition and temperature of the star.Hottest - blue and white, they can have a temperature of more than 50000-60000 ° C.Such as our sun - yellow.They have a temperature of about 5000-6000 ° C.Coldest - is red.They have a temperature of "only" 2000-3000 ° C.
They also differ in size.Which celestial body called supergiants-stars?Those that reach a diameter of almost a billion kilometers.There are neutron stars with a diameter of only 30 kilometers.For comparison, the star Betelgeuse supergiant so large in size that astronomers can easily recognize the shape of its surface, despite the fact that it is removed from our planet at a distance of approximately five hundred light-years.Betelgeuse is so huge that if the sun in diameter would be the same, the edge can easily be reached from Jupiter.But this is not the biggest star!Scientists today are opening new supergiants, several times higher than in the amount of the incredible size of the object.
What we know about our nearest star?
huge ball of red-hot plasma, located in the heart of our system, it is the star - the sun.Astronomy has allowed scientists to learn almost everything about this luminary, without energy which would not be possible existence of life on Earth.
its diameter reaches 1.4 million kilometers, or 109 Earth diameters.Around it moves a lot of comets, dust, asteroids and dwarf planets, as well as the eight planets that form our solar system.
Sun formed 4.5 billion years ago as a result of a giant explosion of one or more stars, after which there was a huge cloud of dust and gas.It is called the solar nebula.Which celestial body called the stars and how they are formed, we have considered above, and on this basis, with the exact safe to say that the sun - it's the closest to the real star of the planet Earth, which distinguishes an incredible amount of nuclear energy and is the center of our solar system.
Conclusion
Starry sky for centuries attracted human views to themselves.Using the best optics allows scientists to not only know what is called the celestial bodies stars and planets, but also to look far into space, for many, many millions of light years, revealing more and more secrets contained in this amazing unexplored space called the universe.
