Planet order

A Journey through our solar system – Astronomy for Kids

Our solar system is an exciting place in our neighbourhood. It has sun as its head and all the members of the solar system like planets, their satellites, meteoroids and comets revolve around the sun in an orbit. The sun, the moon and all those objects shining in the night sky are called celestial  bodies. Some have their  own heat and light, which they emit in large amounts. These celestial bodies are called stars. Infinite number of twinkling stars in the night sky are similar to the sun. But we do not feel their heat or light, and they look so tiny because they are very very far away from us.

Planet order

There are eight planets in the solar system moves around the sun in fixed path and these fixed paths are called orbits. However all the planets in the solar system don’t support life so in order to find is there any other planet apart from our earth which supports life lets go on a journey through the solar system and try to learn more about the planets which are part of the solar system and  we will also try to find is there any planet on which we can try to land so get onto our solar vehicle which will take us through the solar system tighten your seat belts let’s start our journey from the most important member of our solar system that is the sun.

SUN

It’s a fireball. The sun is the nearest star to the earth, sunrays takes eight minutes to reach the earth. Sun usually comprises of helium and hydrogen. The temperature at the centre of the sun reaches upto 15 million degree, it means it is better to stay far far away from the sun we can’t even think of landing on it.

Sun

As the sun is very hot place so let’s move away from the sun quickly as we know Planets revolve around the suns which are large size celestial bodies. When we move away from the sun the first planet we will come across is mercury.

Mercury

It is the nearest planet to the sun. Mercury’s maximum temperature can reach upto  400° Celsius.  Compare this to a warm summer’s day in Delhi, when the maximum temperature might be 45° Celsius. However Mercury’s minimum temperature can go upto -200° Celsius which is extremely cold usually this happens because Mercury has no atmosphere around it to protect it from the Sun it means when sun rays reaches mercury it makes the planet very hot and as soon the sun rays goes all the heat also escapes out into space and this makes the planet very cold and all this happens because of the absence of atmosphere. You would need a very special spacesuit to visit Mercury. So that means mercury is not a happy place to land on so now let’s move away from this planet and the next planet that we will come across will be Venus and now let me inform you about Venus before we land on it.

Mercury

VENUS

Venus is the brightest planet in the Solar System and often it can be seen even in daylight. Venus is the planet which is closest to the Earth. It is also known as twin sister of Earth. Venus is the hottest planet in the Solar System, hotter than Mercury, which is closer to the Sun. The atmosphere on Venus is made up of carbon dioxide. When Venus surface is heated by rays from the sun the heat cannot escape back through the layer of carbon dioxide this is the reason it is the hottest planet. The picture shows how Venus looks in the sky when visible in the morning or evening.

So now would you like to land on this planet I guess no so let’s see which is the next planet and can we land on it certainly yes because our next planet is earth the only planet which supports life lets land onto this planet and take rest in between let me tell you something more about this wonderful planet

EARTH  

It is the only planet that has atmosphere containing oxygen. It is the only planet that has liquid water on its surface. As we know that the Earth orbits round the Sun, it also rotate on its axis and also the earth is tilted by 23.5 degree this is the reason that we have seasons, day and night on earth.  The side of the Earth that faces the Sun has daytime and the other side of the Earth that is not facing the Sun has night-time.  When it is daytime in India, it is night-time on the opposite side of the Earth in America.  The only reason why life is possible on earth is because of the Earth’s atmosphere which has protected the Earth and allowed life to flourish. Because of all the above reasons life is possible on earth and it is our responsibility to protect this wonderful planet which is our home. Image shows the tilt and earth’s rotation around sun, day- night and season’s cycle.

The long but adventurous journey that we started from the sun has reached to earth. Planets have been divided into two parts that means all the planets from mercury to mars are called the inner planets of the solar system and planets from Jupiter to Neptune are called outer planets. It would be a great idea to learn about these planets as well. However I have a good news for you and that is we can learn about these planets without going on another trip on our solar vehicle, you all might be wondering how would that be possible so let me put an end to all your queries. I guess there is hardly anyone not familiar about NASA and we all also know it is a premier organisation working in the field of space and it also launches space programs. In 1977 NASA started a program named as “voyager program” the main objective of the mission was to study the outer planets of our solar system and for that NASA sent two vehicles namely VOYAGER-1 AND VOYAGER-2 in 1977. Voyager-1 was supposed to visit Jupiter and Saturn whereas Voyager-2 was supposed to visit Neptune and Uranus. Voyager 1 and Voyager 2 are identical in construction and that’s why they are called twin. The twin Voyager 1 and 2 spacecraft are exploring where nothing from Earth has flown before. Continuing on their more-than-37-year journey since their launches. They are the farthest manmade object from Earth. Before we start learning about outer planets one inner planet is left out and you guessed it right that is mars. Scientists believe life is possible on mars and why they think so let’s understand it.

MARS

It is often described as the “Red Planet” due to its reddish appearance.  Mars is the second smallest planet in the solar system behind Mercury. Scientists believe life is possible on mars because Mars Had Water in the past because the rocks which are found there can only have  formed in the presence of water.  Scientists are sure that there is ice at the poles of mars similar the way earth poles have. Mars has seasons like Earth. This is because Mars is tilted on its axis by about 25.19 degrees, which is similar to the axial tilt of the Earth (22.5 degrees)

Mars

I keep on imagining how world would be if people start living on mars as well, however right now that prospect is quite far away so what we will do instead let’s focus on what we were doing right now yes we will now learn about outer planets. As the things are becoming more interesting this is the right time to tell you about something which lies between the mars and Jupiter when we move from mars towards Jupiter in between we will come across the belt full of rocks and debris which is named as asteroid belt, Many scientists believe that this debris within the asteroid belt may be from a planet that actually never formed. The asteroid belt sits between the outer planets and the inner planets. All these rocks and debris orbit around the Sun. So this means our solar system is not just about planets it is lot more than that.

Asteroid belt

 JUPITER

Jupiter is the largest and most massive planet in the Solar System. It is so huge that 1000 earths can fit into it. Jupiter has the shortest day of the eight planets. Jupiter is the fourth brightest object in our solar system and it is because of its huge size. After the Sun, the Moon and Venus, Jupiter is the brightest and is one of five planets which can be seen by naked eye from Earth.

Jupiter

SATURN

Saturn is similar to Jupiter, but it is much smaller. It is the second largest planet in our Solar System. It is surrounded by rings that stretches out into space for thousands of kilometres. The most beautiful planet in our solar system (other than earth of course) due to its spectacular ring system. Saturn is most well-known for its rings. The other things to note about Saturn rings are that they are not very thick which gives the planet a good look. The rings are 7 in all. The rings are made up of particles of ice, dust and rocks. Saturn is the furthest planet from Earth that can be seen without the help of a telescope.

Saturn

URANUS

It is the third largest planet in our solar system. Uranus is very cold, windy that means not a happy place to be on. Uranus is sometimes called an ice planet. This is because much of the planet is made up of frozen elements.  Uranus has the coldest atmosphere of all the planets in the Solar System. Uranus has rings like Saturn, but they are thin and dark. Only one spacecraft in the history of spaceflight has ever made a close approach to Uranus. NASA’s Voyager 2 zipped past Uranus in January, 1986.

NEPTUNE

The discovery of the planet Neptune was one of the most exciting discoveries in astronomy. Photos of Neptune reveal a blue planet and this blue color that is partly due to unidentified compound however there are lot of stories to it. Voyager 2 took many pictures of the planet and much of what we know today about Neptune came from this single visit. Neptune is a very windy place. No other planet in the Solar System has winds that are on this planet.

Neptune

Finally our journey is complete and we learnt a lot about our solar system and the planets which are part of the solar system but one question does comes in mind what is beyond the solar system scientists believe the area beyond the Neptune has a belt which they named as Kuiper belt. Kuiper belt is a disc shaped region which also contains dwarf planet like Pluto and comets as well. Astronomers are hunting to find a ninth planet in this belt. The belt is similar to the asteroid belt found between Mars and Jupiter, although the objects in the Kuiper Belt tend to be more icy rather than rocky

 

Kuiper Belt

You might be thinking that now your journey through the solar system is completed however that’s not the case voyager which is providing us all the information about the outer planets it also provided the information about the kuiper belt region but when it went just beyond it our voyager found something else as well and it is called a oort cloud you might be wondering what is it. It is a sort of cloud which surrounds the solar system just like an outer layer. In this oort region there are lot of objects orbiting around the sun but sometimes few objects leaves the oort cloud and enters into inner part of our solar system and when these objects interacts with the sun they become comets. Now i believe you know from where comets come from. Image shows you how comets travel around the sun.

Comet Orbit

Now i am pretty sure you might be thinking that our solar system is not just about planets and sun its beyond that as well it’s hard to cover everything for now we will stop our journey through the solar system and we should thank our solar vehicle and also voyager twins for taking us through the solar system and providing us with all wonderful information about our solar system.  Our journey is almost completed but right now one thing that comes to my mind is the moon and whenever i look up in the night sky one thing that has always astonished me is the moon and i believe most of us do find moon beautiful and we are always curious to know more about it however you will be surprised to know that moon is the natural satellite of our earth and all the planets in our solar system have not just one but more than one moon.  Natural satellites are those celestial bodies which revolve around the planets and follow them in their revolution around the sun. These satellites also receive their heat and light from the sun. The moon is the natural satellite of the earth. Mercury and Venus have no satellites. Mars has two moons — Deimos and Phobos. Table shows how many moons planets have.

planets mercury Venus earth mars Jupiter Saturn Uranus Neptune
Number of moons 0 0 1 2 67 62 27 14

Earth - Moon

As with the passage of time scientists have explored a lot in our solar system however solar system is so vast it will take several years to explore it fully. The more we explore it the more we will learn about our solar system and it will   open more opportunities to the human beings because of various discoveries only in our solar system we are able to send artificial satellites that orbits the earth which provide us lot of useful information and we can say exploring the solar system has been a boon to mankind. It will be important for us to try to explore it further to know more about our solar system.