In our galaxy, and indeed in the entire universe, there is a great variety of different celestial objects. In the night sky, we can observe them in the form of a huge number of twinkling dots and specks surrounding us from all sides. But what celestial bodies are called stars and why do we see their glow?
What are stars?
A star is a very distant, bright and hot giant mass, consisting mainly of helium and hydrogen gases. Due to the huge pressure created inside the star, the nuclei of hydrogen atoms begin to collide with each other, starting a process called nuclear fusion. At the same time, celestial bodies - stars - emit an incredible amount of light, heat and energy.
The main element of a star is hydrogen. As a rule, it contains three times more than helium. The amount of helium directly depends on the size and age of the object: the more helium, the older the star. All other elements make up only 2%, but they help scientists with accuracy.determine the composition, luminosity, temperature, color, size of the star, as well as how far a star can be removed from the Earth.
What color and size can stars be?
Yes, stars come in different colors. Among them are red, orange, yellow and blue. For astronomers, color can tell a lot, and it depends on the composition and temperature of the star. The hottest ones are blue and white and can have temperatures in excess of 50,000-60,000°C. Such as our Sun - yellow. They have a temperature of about 5000-6000°C. The coldest are the red ones. They have a temperature of "only" 2000-3000°C.
They also differ in size. What celestial bodies are called supergiant stars? Those that reach a diameter of almost a billion kilometers. There are also neutron stars with a diameter of only 30 kilometers. For comparison: the supergiant star Betelgeuse is so large in size that astronomers can easily distinguish the outlines of its surface, despite the fact that it is about five hundred light-years away from our planet. Betelgeuse is so huge that if the Sun were the same diameter, its edge would easily reach Jupiter. But this is far from the largest star! Scientists are still discovering new supergiants, several times the size of this incredible object.
What do we know about the nearest star to us?
A huge ball of hot plasma, located in the very center of our system, this is the star -The sun. Astronomy allowed scientists to learn almost everything about this star, without the energy of which life on Earth would not exist.
Its diameter reaches 1,400,000 kilometers, or 109 Earth diameters. There are many comets, dust, asteroids and dwarf planets moving around it, as well as eight planets that form our solar system.
The Sun was formed 4.5 billion years ago as a result of a giant explosion of one or more stars, after which a huge cloud of dust and gas appeared. It is called the protosolar nebula. What celestial bodies are called stars and how they are formed, we considered above, and based on this, with exact certainty it can be argued that the Sun is the real star closest to the planet Earth, releasing an incredible amount of nuclear energy and being the center in our solar system.
Conclusion
The starry sky has attracted human gaze for centuries. The use of the best optical devices allows scientists not only to know what celestial bodies are called stars and planets, but also to look far into space, many, many millions of light years, revealing more and more secrets contained in this amazing unexplored space called the Universe.
