The solar system
The HUB of the Solar System is the Sun. Around it orbit nine planets and their moons, along with a swarm of asteroids (also known as minor planets) and smaller pieces of debris. The sun contains about 99.9 percent of the Solar.
The Sun and Planets
The Solar System is orbiting the center of the Galaxy. At the same time, the planets are in orbit around the Sun, all moving counter clock wise as viewed from over the sun’s North Pole. Each planer also spins in its own axis of rotation. The four innermost planets- Mercury, Venus, Earth and Mars- are small, rocky bodies, sometimes known as the terrestrial planets-Mercury Venus, Earth, and Mars are small, rocky bodies, sometimes as known as the terrestrial planets. Beyond Mars is the asteroid belt and then the gas giants: Jupiter, Saturn, Uranus, and Neptune, so called because they are much larger than the Earth and consist mostly of hydrogen and helium. All four have ring system and numerous moons. Pluto is a small, frozen oddity, which for part of its orbit is closer to the Sun then Neptune is. The planets are thought to have formed Sun about 4.6 billion years ago. Astronomers have found evidence that planets exist around other stars, too.
Orbit of the Inner Planets
The Earth is the largest of the four rocky inner plants. Mercury and Venus, which orbit between the Sun and Earth, are known as inferior plants.
Observing the Planets
The orbits of the Earth and other planets are in much the same plane. As result, the planets in much the same plane. As a result, the planets stay close to an imaginary line called the ecliptic that represents the Sun’s apparent path across the sky over the course of a year. Inferior plants (Mercury and Venus) are always close to the Sun in the sky, appearing before dawn or after sunset, but never in a truly dark sky. Five planets Mercury, Venus, Mars, Jupiter, and Saturn are bright enough to be seen with the naked eye. They can be identified by watching their movement from night to night against the backdrop of seemingly fixed stars, noting how they disturb the shapes of the constellations. The outermost planers are harder to see: Uranus and Neptune can be found with binoculars, but Pluto can be seen only with a telescope.
Opposition and Conjunction
The ease with which most planets can be seen depends on their position in relation to the Sun and Earth. The angle between the Sun and a planet, as seen from the Earth, is known as elongation. At their greatest eastern and western elongations, inferior planets lie in the evening and morning skies respectively. At conjunction (when elongation is zero), a planet is lost in the Sun’s glare. A superior planet can lie opposition; at this time, it looks largest, is visible all night, and at midnight lies due south from northern latitudes and due north from southern latitudes.