A Red Giant Star Facts: Unbelievable Solar System Facts For Kids!

Do you know what is a red giant star? A red giant star is a star that is dying. It is at the last stage of its stellar evolution. Red giants are usually the ‘main sequence star.’

These stars convert hydrogen into helium gas. When a star uses all of its hydrogen, it dies. This process takes billions of years. These stars are over 100 times bigger than the Sun. These main sequence stars will one day become red giant stars and complete the last stage of their stellar evolution.

White dwarfs are other common stars in the universe.

Red giant stars are massive stars. A red giant star's diameter can be hundreds of millions of kilometers. These stars may appear orange or red in color. The temperature at the surface and outer atmosphere of a red giant can be between 4,000°-5,800° F (2,204°-3,204° C). There are various classes of stars like class G, class K, class N, class M, carbon stars, and many others. Our Sun belongs to class G. Other examples of red giant stars are Cacrux (class M), Arcturus (class K), Aldebaran, Hamal, Mira, and various others. Most of these are located in the outer solar system.

Red giant stars are powered by nuclear reactions, for example, the helium fusion process. After around five billion years, our Sun will also become a red giant star the size of Earth's orbit and engulf Mercury and Venus, the inner planets. It is also likely that it might engulf the Earth as well. Red giants are larger but fainter than their parent stars.

As the Sun becomes bigger, the liquid water on the Earth will evaporate marking the end of life and also bringing an end to the habitable zone.

After reading about how long a star takes to become a red giant, also read facts about a puppeteer and a rock made of shells and corals cemented together.

Causes Of Red Giant Stars

Main sequence stars are those which undergo the process of nuclear fusion to convert hydrogen gas into helium gas. When the hydrogen starts running out, these stars turn into red giants. These stars take several billions of years to use up all of their hydrogen.

When hydrogen converts into helium, energy is created which helps the star to keep going and not collapse. After all the hydrogen is used up, there is no energy left. The star is not able to survive and starts collapsing. During this phenomenon, the star also lights up. The helium atoms now start combining to form carbon.

This process also produces energy that stops the collapsing of the star. Outer layers of the star are pushed outwards which results in a much larger star. It is orange or red in color and is known as a red giant star. After the red giant phase, it becomes a white dwarf and eventually dies.

Will our Sun ever become a red giant?

The Sun is a main sequence star, which means that it converts hydrogen into helium by a process known as nuclear fusion. Ultimately, in approximately 5 billion years, it will turn into a red giant star. When this red giant phase is over it will eventually die after 5 billion more years.

The Sun is approximately 4.6 billion years old. It is the main source of energy for Earth and various other planets in our solar system. Scientists are not sure how adversely it will affect our planet, but surely there will be no life left by then. The Sun gets its energy by undergoing a nuclear fusion reaction to convert hydrogen atoms into helium atoms. Just like other main sequence stars, the Sun has limited hydrogen in its core which will eventually run out.

The time depends upon the size of the star. The Sun will run out of its fuel in about 5 billion years and become a red giant star. It will then shrink into a white dwarf, then into a planetary nebula, and eventually die.

Now, how will these phenomena affect the planet nearest to the Sun, Mercury? When the Sun turns into a red giant, it will also increase in size. It will be so huge that it will engulf the foremost planets of our solar system like Mercury and Venus.

When The Sun Will Become A Red Giant

The Sun will eventually become a red giant star and die. It is inevitable. But we humans won’t be there to witness it. We will be long gone by then. It will take approximately 5 billion years for the Sun to become a red giant. With its increasing intensity every year due to the helium flash, we will be gone in the distant future.

The Sun has hydrogen in its entire core and has high surface temperatures. This hydrogen converts into helium through a nuclear fusion reaction. This whole process produces energy that helps the star to resist gravity and not collapse. But there is limited hydrogen available. When this hydrogen runs out and all of it is converted into helium, the star collapses as there is no energy left to resist the gravitational pull. At this time, helium atoms start reacting among themselves to form carbon atoms.

This reaction then produces energy and stops the star from collapsing. It becomes a red giant and appears red or yellow-orange in color. This red giant increases in shape and diameter and engulfs the planets orbiting it.

Our Sun will engulf Mercury, and possibly Venus and Earth too. After its energy is used up, it will shrink and become a white dwarf. Then it will turn into a planetary nebula and eventually die. It will take about 10 billion years for the Sun to die completely.

Which is the biggest star in the universe?

The biggest star in the universe is known to be UY Scuti. It is a red hypergiant. It is located in a constellation named Scutum. It is approximately 5 billion times bigger than the Sun in volume.

Its radius is about 1,700 times longer than that of the Sun. It is a dying star.

It was first observed by German astronomers working at the Bonn Observatory in 1860. When it was observed for the second time, these astronomers noticed that its brightness had increased. It was classified as a variable star. A variable star is a star whose brightness can change or fluctuate when observed from the Earth. It has a pulsation period of 740 days. Since UY Scuti is a red giant, it will soon die. It has about 10% or a few million years left of its life span. It is expected that when it will die, an explosion of more than 100 supernovas will take place.

More massive stars are KW Sagitarii, V354 Cephel, and KY Cygni.

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