Galaxies are a vast collection of billions of solar systems. Our earth is part of a solar system making up the Milky Way galaxy. Our solar system consists of the sun, planets and other heavenly bodies. The planets that make up our solar system are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune. Other objects that make up our solar system are satellites, meteoroids, comets, and asteroids.
The earth and other heavenly bodies are in a regular pattern. That way, the earth does not collide with other heavenly bodies. Everything, directly and indirectly, circulates around the sun. lots of other things that are similar to the sun. Stars in the flickering sky are in the same position as the sun. The stars also have certain planetary arrangements such as the solar system.
The sun is classified as a star because it radiates its own light. The sun is surrounded by planets because the sun’s gravity is very large, the sun is a glowing ball of gas. The surface temperature is about 6,000 6C, while the inside is even hotter, which is about 15 million˚C. its diameter is approximately 109 times the diameter of the earth, and it is located approximately 150 million km from our earth. the sun is a celestial body that emits its own light. Therefore, the sun is also called a light source or star.
Apart from the sun, sometimes we see in the sky objects that move between the stars. Such objects are called planets. What is the difference between planets and stars? So planets are celestial bodies that don’t have their own light and planets only reflect light from stars. When observed planets do not flicker, whereas stars always flicker. In August 2006, world-class astronomers agreed on new rules for understanding planets, namely:
• The planet is a celestial body that orbits around a star and is not itself a star.
• Planets are so large that they are able to maintain a round shape like a ball.
• Planets’ orbits should not be in contact with the orbits of their neighboring planets.
We already know that there are nine planets accompanying the sun. The nine planets are Mercury, Venus, Earth, Mars, Jupiter, Saturn and Pluto. Based on the new rules about the understanding of the planet, the planet Pluto is no longer included in the group of planets. This is caused because the orbit of Pluto is in contact with the orbit of Neptunus. So, the solar system now only has eight planets around the sun. The planets surround the sun because of the sun’s gravity force. The force of the sun’s gravity is greater than the force of gravity of the planets. Therefore planets revolve around the sun, not vice versa.
Based on the location of the orbit, the planets are classified into two parts, namely the inner and outer planets. Inner planets are planets whose circular paths are between the sun and the earth, including the inner planets are Mercury and Venus. Outer planets are planets whose paths are outside the circulation of the earth, namely: Mars, Jupiter, Saturnus, Uranus, and Neptune. Of the eight planets that exist, planets that we can see without using tools other than Earth are Mercury, Venus, Mars, Jupiter, and Saturn. Meanwhile, to see other planets, we must use binoculars or telescopes.
Satellites are celestial bodies that accompany the planets as long as the planets circle the sun. Satellites move (circulate) around their respective planets. Therefore, satellites are also called planet companions. Natural satellites are satellites that naturally exist to accompany various planets and were not created or created by humans. While artificial satellites are satellites deliberately made by humans and launched into space for certain purposes using rockets. There are several planets that have natural satellites, for example, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune. There are different amounts of natural satellites on every planet. Earth has 1 satellite, Mars 2 satellites, Jupiter 16 satellites, Saturn 18 planets, Uranus 15 satellites, and Neptune 8 satellites. The number of natural satellites can change with the discovery of other satellites using even more modern technology.
Meteorites are objects that hover in outer space. This object is composed of very small rocks. Meteorites that are too close to the earth can be affected by the attraction of the earth and enter the earth’s atmosphere. When entering the Earth’s atmosphere, the meteorite will rub against the air to cause sparks. Glowing meteoroids move fast and appear as falling stars or switching stars or so-called meteors.
When entering the Earth’s atmosphere, a meteorite can burn out before it reaches the earth’s surface. But there are also meteorite fragments that entered the earth. Meteorite fragments in the form of chunks of black stone and hard called a meteorite. Meteorite fragments that hit the surface of the earth can cause a huge explosion and leave scars like craters. For example the Barringer crater in Arizona, United States.
Comets are small solar system bodies, usually only a few kilometers in size, and are made of volatile ice. According to another book, a comet is a celestial body that surrounds the sun with a circular line or orbit that is very oval-shaped and resembles a star. Comets have their own light and also reflect sunlight. Therefore, comets appear glowing and have tails of light. So the comet is also called a tailed star.
When a comet enters the inner solar system, its closeness to the sun causes the ice surface to sublimate and ionize, which results in comas, gas tails and long dust, which can often be seen with the naked eye. And as it approaches the sun, the comet gets a boost of the sun’s wind so that its glowing tail is behind it. Comets consist of a collection of dust and gas that can freeze away from the sun. The comet’s tail always approaches the sun. When the comet moves toward the sun, its tail is behind. Whereas when the comet moves around the sun, its tail is in front. Comet tail length reaches millions of kilometers. The closer to the sun, the longer the comet’s tail. Comets that appear in our solar system can be seen in uncertain times. Some comets that are already known: Encke comets appear every 3 years, Halley comets, appear every 76 years, etc.
Asteroid or Planetoid
Asteroids or Planetoids are small celestial bodies that surround the sun at certain trajectories. Asteroids, in general, are solar system objects consisting of igneous rocks and mineral minerals. Asteroid’s graduation is hundreds of kilometers to microscopic in all asteroids except the largest ceres. The shape of the sides is irregular so people say that asteroids are fragments of a celestial body.