Most likely, you do not know much about planets or stars. I will tell you about stars and planets first, though. But you should never forget that the sky is home to a vast array of other objects. Furthermore, galaxies that gather a large number of stars will be covered. Specifically, we will examine our galaxy—a galaxy to which we are members. And what else will we discover? In this course, among many other topics, we will study asteroids, cosmic rocks, comets, shooting stars, and much more. Among many other celestial objects, we will study black holes, enigmatic neutron stars, and irresistible gravitational pulls. You will have the opportunity to get to know some outstanding astronomers and scientists as you study step by step. After observing objects in the sky and analyzing their observations, astronomers and scientists developed a theory. Additionally, through a variety of experiments, they made it easier for us to comprehend the Earth and the phenomena that surround it.
Let us begin by discussing the stars.
Tens of thousands of stars can be seen if you examine the night sky closely. However, that figure only represents what our eyes can reasonably estimate. We can see trillions of stars, not thousands, if our eyes are limitless. You can probably guess how many there are since there are 12 zeros in a group.
The stars are what, then?
A star is, astronomically speaking, a star that emits light on its own, similar to the sun. In a large sense, a star refers to the sun, planets, satellites, etc. floating in the sky.
For a star to be able to emit light on its own, it must be a massive ball of fire that combines gases like helium and hydrogen (though not much calcium or iron). These stars produce the light that proves stars exist when they burst into explosions for millions or even tens of millions of years. Why do some stars burn longer than others? Some stars have a year-long burn.
As you think stars are still burning gas, they get extremely hot. Stars slowly die from long-term gas exhaustion, much like an automobile that runs out of fuel, fumes, and eventually stops. Naturally, doing that involves a lot of work and steps.
Young stars in the process of developing are called protostars. As gas and dust build up, stars begin to progressively become heavier, even though they do not yet burn or emit light. The birth of a true star is imminent.
When a star gathers enough material, the foreign matter inside of it clumps together and explodes, releasing light. In our world, it becomes a real star. Those stars that never make it to this stage are known as brown dwarfs; they are just lumps of black gas and dust without any light.
Starlight gradually diminishes as stars age, but they continue to grow in size. Giants are stars that reach this stage. Blue giants, which burn at the fastest rate and have a life span of only millions of years, are the hottest and brightest stars in the universe.
The largest stars, known as supergiants, have the potential to grow up to 1,000 times bigger than the sun.
Before they completely burn out, some stars undergo a size reduction and become white dwarfs. When they exhaust all of their fuel, they transform from white dwarfs to black dwarfs.
At the end of their lives, famous people also have a glamorous appearance. Their explosion turns them into a supernova rather than a dwarf star. Large explosions such as this one rarely occur, but they usually last for weeks.
A binary star is a star system in which two stars are attracted to each other and orbit at regular intervals around a common center of gravity. There are three types of binary stars: the eclipse binary, the spectral binary, and the orbital binary. An eclipse binary cannot be located even with a large telescope, but one can observe an orbital binary. One can distinguish binary stars—two stars that are invisible to the unaided eye—from other stars using the spectrum of the star Algol, which is represented by in the Perseus constellation.