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The night sky is full of tiny, glimmering things, some bright and some dull. All of them seem to be blinking. Once every month or so, there is a full moon known as Full Moon Night or Poornima. When the moon is completely hidden a fortnight later, it is known as New Moon Night or Amavasya.
Celestial bodies are anything that shines in the night sky, including the sun, the moon, and other luminaries. Some asteroids are enormous and extremely hot. Gases make up their composition.
Stars – Stars are celestial bodies that produce a lot of light and heat on their own. A star is the sun.
Constellations: Different groups of stars, known as constellations, create a variety of designs in the night sky. One such constellation is Ursa Major, or the Big Bear.
The Saptarishi is one of the most recognisable constellations (Saptaseven, rishi-sages). It is a collection of seven stars that belongs to the constellation Ursa Major.
The stars were employed in ancient times to help people find their way at night. The North star points in the direction of the North. The Pole Star is another name for it. It stays in the same spot in the sky at all times.
The celestial bodies known as planets lack their own heat and light. They are illuminated by the starlight. The Greek word “Planetai” is where the term “planet” originates.
The solar system is made up of the sun, eight planets, satellites, and a few other asteroids and meteoroids.
The Sun- The solar system’s centre is the sun. It is enormous and composed of incredibly hot gases. It supplies the gravitational pull that holds the solar system together. The solar system’s primary source of heat and light is the sun. About 150 million kilometres separate Earth and the sun.
In our solar system, there are eight planets. They are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune in order of their distance from the sun. The solar system’s eight planets all follow set routes as they round the sun. Orbits are the names for these pathways.
Earth- The third planet from the sun is the earth. It is the fifth-largest planet in terms of size. At the poles, it is slightly flattened. The Geoid shape of the Earth is referred to. Only on Earth are there likely to be conditions that allow for life. It has air and water, two things that are vital for living. Life-sustaining gases like oxygen are present in the air. The earth appears blue from space because water covers two thirds of its surface. It also goes by the name “blue planet.”
Moon- The moon is a satellite of the earth. It merely has a fourth the diameter of the earth. Because it is closer to our planet than other celestial bodies, it appears to be much larger. About 3,84,400 kilometres separate us from it. It takes the moon around 27 days to orbit the earth. One spin takes precisely the same amount of time. As a result, we can only see one side of the moon from the earth. There are no favourable environmental factors on the moon for life. On its surface, there are mountains, plains, and depressions. On the surface of the moon, these created shadows.
Asteroids- Small bodies known as asteroids orbit the sun. They can be located in the space between Mars and Jupiter’s orbits. According to scientists, asteroids were once a planet that exploded long ago.
Meteroids- The term “meteoroids” refers to the tiny rocks that orbit the sun. These meteoroids occasionally approach the earth and have a tendency to fall upon it. They heat up and burn during this process because of friction with the air. A bright flash results from it. On occasion, a meteor that hasn’t burned through fully hits the ground and leaves a hollow.