Did you know that there are more stars than grains of sand on Earth?
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There are more than 100 billion in our galaxy alone star, and do you know how many there are in the entire universe? Have you ever wondered why they flicker? Do you know what color the sun is? Don’t miss to read below some interesting facts about these glowing balls.
Why do the stars twinkle?
If you look at the night sky, you will notice that the stars “twinkle”. However, this is not a characteristic of the stars themselves, but an illusion caused by the existence of an atmosphere on our planet.
Different layers of the atmosphere, with their different temperatures, densities, composition and air movement, have a great influence on how we see the light of distant stars that reaches us. As he passes through them, light is constantly refracted and scattered, which for an observer from Earth creates a flickering effect, which is especially pronounced if the stars are observed close to the horizon.
To reduce the influence of the atmosphere, astronomers use various systems in their telescopes, such as adaptive optics, or launch them into space, where they can getmuch clearer and more stable observations of stars, planets, galaxies and other objects.
The sun is not yellow
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Another illusion caused by the influence of our atmosphere is that we see the Sun as yellow. However, the true color of our star is white. Just as a prism separates sunlight into rainbow colors, our atmosphere “behaves” similarly.
Air molecules in our atmosphere scatter shorter wavelengths of the visible spectrum more efficiently, which gives our sky its characteristic blue color. Conversely, longer wavelengths, including yellow and orange, are scattered less and reach our eyes directly, giving the Sun its familiar, warm glow.
There are more stars in the universe than there are grains of sand on Earth
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It is not possible to count all the grains of sand on Earth, but according to the calculation of scientists who took into account all the sandy surfaces on the planet, the estimate of their number is about 7.5 trillion. It is also not possible to count all the stars, but NASA claims that according to their rough estimate, this number is significantly more than the number of grains of sand, i.e. about 1 quadrillion.
The stars are rapidly disappearing from the night sky
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Unfortunately, although we all love to see a sky full of stars, there are fewer and fewer of them visible to the naked eye, and their number is rapidly decreasing.
According to a study published at the beginning of the year, based on more than 51,000 observations, it was determined that the number of stars visible to the naked eye decreased in the period from 2011 to 2022 by 7 to 10 percenta the reason is increased “pollution” by light due to the growth of the population, the expansion of cities, as well as the massive use of LED lighting.
If this trend continues, the region where 250 stars can be seen with the naked eye will have only 100 visible stars in 18 years.
(World)