The Earth’s Atmosphere It is the Atmosphere which has made life possible on the Earth, it protects us from the harmful rays of the Sun and keeps out the cold of outer space, and it also provides a host of other conditions because of which life can thrive on this planet. It has various layers and surrounds the Earth like an insulator, 78% of it is composed of Nitrogen, 21% of...

Earth’s Crust and Inner Core Millions of years after it’s origin, the Earth still has a molten core, about 2600 km thick, with a temperature in the range of 4,700° centigrade. Above this inner core is an outer core which is about 2,000 kms thick and is made up of molten iron with temperatures in the range of 2,2000 centigrade. The ‘Mantle’, as it is called, which surrounds both the inner...

Our Satellite the Moon It was believed earlier that the Moon was a piece of the Earth which broke away millions of years ago. This theory went through a change as new facts about the Moon were revealed with the passage of time. Today it is believed that the Moon was formed from the same cloud of dust from which the Earth was formed. The Moon also went through the same...

The Earth Our planet, the Earth, is a part of the Sun’s family and is located about 150 million km away from it. The Sun was formed due to the contraction of a cloud of gas and dust, the remaining part of this cloud eventually formed the other planets in the same manner. The Earth took close to 100 million years to become a glowing ball comprising of molten rock. The...

The Ozone Layer The Earth’s atmosphere comprises of various layers, the first which extends up to 10 km from the Earth’s surface is the Troposphere’. Above this is the ‘Stratosphere’ which is between 10 and 50 km, then the `Mesosphere’ between 50 and 80 km and finally there is the  ‘Ionosphere which is located between 80 and 501) km from the Earth’s surface with temperatures as high as 2000° centigrade. About...

Life on Earth Unlike other planets and even our own moon, the Earth has relatively stable temperature conditions and compared to other planets it doesn’t become too hot or cold. This is primarily possible because of the Earth’s atmosphere which acts like a shield. The presence of large quantities of water and oxygen also contribute to the existence of life on Earth. Besides this the Earth’s atmosphere has a layer of...

The Weight of Our Atmosphere Just as an orange is surrounded by peel, the Earth is surrounded all around by a 640 km thick shell of air. This shell can be broken down into various layers and it comprises of about 20 different types of gases out of which Nitrogen and Oxygen have the highest percentage. Without the atmosphere it would be impossible to live on the Earth since it protects...

The Size of The Universe Considering the size of our Milky way and the number of other galaxies known to man it is impossible for the human mind to imagine what the size of the universe might be. To start with we cannot even measure distances in space in miles or kilometres, we have to use light years, i.e. the amount of distance light would travel in a year at its...