Find out why the stars shine
One of the natural phenomena that have most astonished man since the beginning of time is the brightness of the stars in a clear sky. Since ancient times, many authors have written works about its beauty, possible origin, etc.
In this lesson from a TEACHER we will see what stars are, Why do stars shine, why the stars shine at night but not during the day or why some shine more than others. If you want to answer all these questions, we invite you to continue reading!
Index
- What are the stars?
- Examples of stars we see shining from Earth
- Find out why the stars shine
- Why do the stars shine at night but not during the day?
- Why do some stars shine more than others?
What are the stars?
The stars They are celestial bodies which are characterized by being a large plasma ball that is formed by a large amount of gas, mainly hydrogen and helium, in incandescent state. This is because they have a mass capable of sustaining nuclear fusion in their nucleus.
This characteristic is precisely what makes them different from the planets. The big difference between stars and planets is that the latter simply reflect light while stars they produce it by themselves thanks, as we will see below, to the reactions that take place within them.
Examples of stars that we see shining from Earth.
The most visible star from Earth is the Sun. The Sun is the main star of our galaxy, the Solar system. But the Sun is not the only star, other stars are also visible from Earth on a clear clear night.
Leaving aside the sun, Proxima Centauri is the closest star, is 4.3 light years from us, while the brightest star we see in the sky is Sirius which is about 9 light years from our planet.
To distinguish a star from a planet, when we look at the sky we must notice if the light blinks. The main characteristic is that the light of the planet is that it does not flicker, since this is a reflected light; Instead, the light of the stars does flicker.
A particularly curious example is that of supernovae or star deaths. The last one that could be seen with the naked eye from our planet was in 1987, and it could be seen as a very intense glow. This is because they are explosions so powerful that they cause a light brighter than all the light in the galaxy that houses them, and therefore they stand out from the rest of the brightness of the sky. It is a peculiar phenomenon and, although it is frequent in the universe, it is not often that we can observe it with the naked eye from Earth, since the supernova must be in a nearby galaxy.
Image: BOCES Newsletter
Find out why the stars shine.
As we have already advanced in the previous point, the stars shine because they are a huge nuclear reactor, inside which reactions are produced that generate a lot, but really a lot of heat. At the center of these, there are atoms separating constantly as a result of giant atomic collisions.
These reactions are called fusion reactions and they generate a large amount of energy. These fusion reactions convert hydrogen atoms into helium atoms and these eventually release a large amount of energy. That energy generated inside the star makes it have extremely high temperatures and therefore the stars shine.
The complete reaction is called nuclear fusion, since the nuclei of the atoms fuse to form a new and heavier nucleus. During it, matter is not conserved, it takes on a plasmatic state, since a large part of it is transformed into energy. This is why stars are celestial bodies in plasma form.
Why do the stars shine at night but not during the day?
A very widespread mistake is to believe that the stars shine us during the day, and they only do so at night. As seen so far, you can assume that of course there are stars during the day, the same as at night. But then why can't we see them? We simply cannot see them due to excess light from the Sun, our own star.
Although the light of the stars reaches us also during the day, its brightness is completely blurred because from excess sunlight in the atmosphere, making it impossible to see them even if the stars are still shining. On the contrary, as night falls and the atmospheric light diminishes, we can begin to see how the stars gradually begin to appear in the sky, filling the sky with white and luminous dots in a night with the sky clear.
Why do some stars shine more than others?
When we observe a clear starry sky, we realize that not all stars shine with the same intensity.
This is because all the stars are not all the same distance from us. Some stars are closer and some are further away. The closer a star is to us, the brighter it will shine.
In addition to this, stars have a great variety of sizes and generate more or less light, depending on the conditions of the star itself (mass, components, etc.) or celestial bodies that may interfere with observation from the Land.
Larger stars usually shine brighter than smaller stars. Mainly, how strongly a star shines in the night sky depends on its size and how far it is from us.
If you want to read more articles similar to Why do stars shine, we recommend that you enter our category of Astronomy.
Bibliography
- Arriols, E (s.f) Why the stars shine at night and not during the day. Green ecology.
- Hermans-Killam, L (s.f) Why are some stars bright and others faint? Ask an astronomer, for kids.
- Posta (May 25, 2017) Why do the stars shine?
