The system consysting of Sun and other objects(planets, moons, asteroids and comets etc) rotating around sun because of it’s gravitational pull is called as “Solar System”. 🌞
The Sun is the only star and at the center of the Solar System. 🌝The largest eaight bodies which rotate around the Sun directly are called as planets of the sun. The moons are those which rotate around a planet and so indirectly rotate around the Sun. There are two moons bigger than the smallest planet mercury. The galaxy of which the Solar System is part of is called ‘The Milky Way’.🌌The Solar System is beleived to be formed 4.57 billion years ago.Sun and it’s Planets:
Sun and it’s Planets are shown in below picture. The sizes of the objects in below picture are relatively correct but distances of planets from Sun are not correct.
🌏NameDistance 👉from Sun mean radius Number of Moons
1Sun(Star)0 AU*2,439.7 kmN/A**
2Mercury(Planet)0.4 AU2,439.7 km0 3Venus(Planet)0.7 AU6,051.8 km0 4Earth(Planet)1 AU6,371.0 km1 5Mars(Planet)1.5 AU3,389.5 km2 6Jupiter(Planet)5.2 AU69,911 km67 7Saturn(Planet)9.5 AU58,232 km62 8Uranus(Planet)19.2 AU25,362 km27 9Neptune(Planet)30.1 AU24,622 km14 AU* – Astronomical Unit : Distance from Earth to the Sun is counted as 1 AU N/A* :
🌞1- Sun : The Sun is the only star and energy source of solar system. It is largest body of solar system and located at the center of the solar system and all other planets rotates around it. Sun’s diameter is about 109 times than that of Earth that means if earth’s is cosidered to be a marble of 1cm diameter the sun will be a massive sphere hsving diameter larger than a metre. Sun 330,000 times more massive than Earth. Around 75% of the mass of Sum cosists of Hydrogen and rest of the mass is of Helium. It also has very smaller quantities of of heavier elements, including oxygen, carbon, neon and iron. 4 Terrestrial Planets orbiting nearer to Sun: The four closer planets to the sun and inside the ateroid belt namely Mercury, Venus, Earth and Mars are Terrestrial in nature. Mainly silicates form their upper layer and heavy metals such as iron and nickel form their core. Except Mercury all other three planets has atmosphere.
2- Mercury :Mercury is the closest planet to the Sun. It is also the smallest of all 8 planets in the Solar System. It has no atmosphere and Natural Satellites.
3-Venus :Venus is the second planet and slightly smaller in size to the earth. It also has dense atmosphere surrounding it. Venus has no natural satellites.
3-Earth :Earth is the third and very special planet of Solar System because it is the only object in Solar System on which life is found. It is our home planet. It is largest and densest of the inner 4 terrestrial planets. It has one natural satellite ‘The Moon’
4-Mars : Mars is the fourth planet from the Sun. It is slightly smaller in size to Earth and Venus. It has atmosphere mainly of Carbon Dioxide. It is red in color because of the large content of iron dioxide in its soil. 2 Gas and 2 Ice Giants in the
**outer part of Solar System:The outer region of solar system has 2 gas giants namely Jupiter and Saturn and two ice giants Uranus and Neptun. Jupiter and Saturn are called gas giants because they are composed of gases mainly Hydrogen and Helium and they are very large in volume and masses. Jupiter is the largest planet and second largest object only after Sun in the solar system. Uranus and Neptune composed mainly of heavier volatile substances which are referred to as ‘ices’ and that’s why they are called ice giants.
**5-Jupiter :It is the largest planet in our Solar System. Jupiter has 318 times more mass than that of earth. It is so large that it has 2.5 times more mass than all other solar system planets put together. It is composed largely of hydrogen and helium. Jupiter has 67 known satellites. Ganymede, on of the stellites of Jupiter is the largest satellite in the Solar System, is larger than Mercury.
**6-Saturn :This is another giant gas planet and second largest planet in the Solar System. It has 95 times the mass of Earth. It is least dense planet in Solar System as it has larger volume but comparitively less mass. Saturn is distinctively known for the ring system it possess. The rings of Saturn are made up of small ice and rock particles. Titan, the largest satellite of Saturn and the second-largest moon in the Solar System, is larger than Mercury and the only satellite in the Solar System with a substantial atmosphere.
7-*Uranus : Uranus the planet after Saturn is first ice giant in solar system. It is 14 times massive than earth. Though it is larger in volume than next ice giant Neptune it is slighter than Neptune. It is the coldest planet in the solar system. Uranus has 27 known satellites. Titania is the largest satellite of Uranus.
8-Neptune : This is the 8th planet in solar system and 2nd ice giant after Uranus. It is 17 times massive than earth. Though it is massive than Uranus it is smaller in size and the smallest in outer four giant planets. Neptune has 14 known satellites. Triton is the largest satellite of Neptune. Other objects in Solar System:
9-Dwarf Planets : A solar system object rotating around the sun which do not have enough gavitaional force to clear it’s neighbourhood meaning it has other objects cmparable to it’s size in the path of it’s orbit around the Sun. Pluto before 2006 was cosidered as planet but now new similar objects are found in the orbit of pluto creating Kuiper belt so now plut is considered as dwarf planet.
***The International Astronomical Union (IAU) currently recognizes five dwarf planets namely Ceres, Pluto, Haumea, Makemake, and Eris. Asteroid belt : Asteroids are small Solar System bodies having diameter of few metres to hundreds of kilometres and are composed mainly of refractory rocky and metallic minerals, with some ice. Asteroid belt exits between Mars and Jupiter, between 2.3 and 3.3 AU from the Sun. It is occupied by numerous irregularly shaped bodies called asteroids or minor planets. It is considered as remnants of solar system formation which failed to come together to form a planet because of interference of Jupiter’s gravitational interference. Comets: Comets are small Solar System bodies, only a few kilometres across, composed largely of volatile ices. They have highly eccentric orbits, generally a perihelion* within the orbits of the inner planets and an aphelion* far beyond Pluto. When a comet enters the inner Solar System, its proximity to the Sun causes its icy surface to sublimate and ionise, creating a coma, a long tail of gas and dust often visible to the naked eye. Note: *In an orbit of an object around the sun perihelion is the point where the distance of the object from Sun is shortest and aphelion is the point where the distance is longest.