He Solar system It is formed by a central star, the Sun, the bodies that accompany it and the space that remains between them.
Eight planets they revolve in orbits around the Sun: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune.
Earth is our planet and has a satellite, the Moon. Some planets have satellites spinning around them, others don't.
Asteroids are smaller rocks that also revolve around the Sun, mostly between Mars and Jupiter. In addition, there are comets that approach and move far from the Sun.
Sometimes fragments of extraterrestrial matter that come from the Solar System or beyond reach Earth. Most light and disintegrate when they enter the atmosphere. They are the meteorites.
The planets with their satellites, and also the asteroids, revolve around the Sun in the same direction, in almost circular orbits. If we could observe from the top of the north pole of the Sun, we would see that the planets orbit counterclockwise.
Almost all the planets orbit around the Sun in the same plane, called ecliptic. The dwarf planet Pluto is a special case, since its orbit is the most inclined and the most elliptical of all. Until recently it was considered a planet, but not anymore. The axis of rotation of many of these planets is almost perpendicular to the ecliptic. The exceptions are Uranus and Pluto, which are tilted to their sides.
Sizes and distances in the Solar System
The Sun contains 99.85% of the matter in the Solar System, almost all. The planets, which condensed from the same material from which the Sun is formed, contain only 0.135% of the solar system's mass. The eldest, Jupiter, contains more than twice the matter of all the other planets together. The satellites of planets, comets, asteroids, meteoroids, and the interplanetary medium make up the remaining 0.015%.
Almost the entire Solar System, by volume, seems to be an empty space that we call "interplanetary medium." It includes various forms of energy and contains, above all, interplanetary dust and gas.
To understand the sizes and distances in the Solar System, let's talk about football. If the Sun were a ball located in the center of the goal, Mercury would be 9 meters, 2 meters before the penalty spot, and it would be like a pinhead. Venus would be at the outer edge of the area, 17 meters from the goal, and would be 2 millimeters in diameter, like a bearing ball.
The Earth would be the same size as Venus and would be 25 meters, more or less, a quarter of a field, which is usually about 90 meters long. Mars would measure only 1 mm, half of the Earth, and would be 10 meters beyond, 35 from the Sun, almost in the center of the field.
The asteroid belt would be in the other goal, virtually invisible, made up of a few and scattered fine grains of sand. Jupiter would be at the bottom of the stands or on the outer wall of the stadium, 125 meters from the goal and 2.5 cm in diameter, a large marble.
To find Saturn we would have to look for a marble of about 2 cm located at the bottom of the parking lot, 100 meters beyond Jupiter, 225 of the ball that represents the Sun. Uranus, an 8 mm olive bone would be around the neighborhood, to 460 meters from the Sun, and Neptune about 250 meters beyond, 710 from the Sun and somewhat smaller than Uranus (a little bony arbequina).
The limit of the Solar System, the heliopause, it would be just over 2.5 kilometers from the stadium, some 16,000 million real kilometers.
Knowing the Solar System
We humans have always observed the sky. First, with the naked eye; later, with instruments. A little over 300 years ago telescopes were invented. But the real exploration of space did not begin until the second half of the 20th century.
Since then many ships have been launched. The astronauts have walked the moon. Vehicles equipped with instruments have visited some planets and have crossed the Solar System.
Beyond the limits of our System, the closest star is Alfa Centauro. It's light takes 4.3 years to get here. She and the Sun are only two among the 200,000,000,000 (two hundred billion) stars that make up the Milky Way, our Galaxy.
There are millions of galaxies that move through intergalactic space. Together they form the Universe, whose limits we still do not know. But astronomers continue to investigate ...
• VIDEO: The Solar System. Educational Videos for Children
• The Solar System according to Wikipedia
|◄ Previous||Next ►|
|What is the solar system?||How did the solar system form?|