Question

Explain the Solar system in detail.

Answer 1

Solar system is defined as a system of bodies under the gravitational pull of a star or Sun in which the bodies eventually orbit the Sun directly or indirectly. There are many solar systems in our galaxy while we know accurately about our own solar system.

Complete step by step solution:
Let us discuss our solar system.
Our solar system was formed about $4.6$ billion years ago due to the gravitational collapse of a giant interstellar molecular cloud.
In our solar system, we orbit the Sun because the Sun is the body with the largest mass in our solar system and hence all objects fall under its gravitational pull ,up to which its gravitational force is felt, and hence orbits it. The bodies which orbit the Sun and revolve around it in periodic motion are known as planets.
The planets are also of big mass which pulls smaller masses to orbit themselves under the gravitational field. Those smaller masses are termed as natural satellites.

Let us now describe everything here:
We look towards the right to the Sun and define them:
A. The Sun: The Sun is the star which is at the center of our Solar system. It is a nearly perfect sphere of hot plasma . It is by far the most important source of energy for life on Earth. Its diameter is about $1.39$ million kilometres which is approximately $109$ times that of Earth. The mass of the Sun is about $3,30,000$ times that of Earth. It accounts for about $99.86\%$ of the total mass of the Solar System.
B. Mercury: It is the closest planet to the Sun in our Solar system. It is the smallest planet in our solar system. It has no natural satellite or moon.
C. Venus: It is a planet which is quite similar to the mass of the Earth. It is the hottest planet in our solar system. The air of Venus is about ninety times denser than the Earth.
D. Earth: The only planet in the solar system where life is known to exist. It is the only planet where plate tectonic movements are also observed. Its atmosphere is quite different from other planets and contains about $21\%$ of free oxygen which is till now not observed anywhere else. It has one natural satellite and we call it the Moon.
E. Mars: Mars also known as the red planet. The red colour of Mars is due to the presence of iron oxide in its soil. Its surface has some volcanoes which seem to have persisted till $2$ million years ago. It has two natural satellites namely Phobos and Deimos.
F. Asteroid belt: It is a belt where small solar system bodies namely asteroids are meant to exist. It is believed that the asteroids were the remnants from the Solar System’s formation and hence failed to collapse due to the gravitational pull of Jupiter. The asteroid belt comprises tens of thousands of objects in a diameter range of about $1$ km. Ceres is the largest asteroid.
G: Jupiter: The largest planet in our solar system which is about $2.5$ times the total mass of all planets together. Jupiter is known to have $79$ satellites. The four largest are Ganymede, Callisto, lo and Europa. Ganymede is even larger than Mercury.
H. Saturn: Mostly known due to the presence of rings around it. Saturn is the only planet known which is less dense than water. Saturn has $82$ known satellites. The second largest satellite, Titan is larger than mercury and known to be the only satellite with a substantial atmosphere.
G: Uranus: Uranus is the lightest of outer planets. Uniquely among planets it orbits the Sun with an axial tilt of over ${90^ \circ }$ with the elliptic. It has $27$ known satellites.
H. Neptune: The last planet of our solar system. It has $14$ known satellites. Triton, the largest known satellite which moves in retrograde motion. Neptune is accompanied in its orbit by many minor planets known as Neptune trojans.

Note: The first four planets closest to the Sun are also known as inner planets and those farther from the Sun or after the Asteroid belt are known as outer planets. Pluto was considered the ninth planet before $2006$ which changed when the definition of planet was altered. It has a tilted axis and revolves two times around the Sun for every three Neptunian orbits.