Comets Comets are visible at night and they look very much like meteors and meteorites but in reality they are different. When we see a comet in the sky we notice that it has a bright head and a glowing tail following it as it shoots across the sky. On a closer examination through a telescope we see a bright head, called the ‘coma’ and a large cloud of glowing dust...

Meteors and Meteorites A meteor is what we commonly known as a shooting star. Millions of small pieces of rock, some only as large as a marble, are orbiting the sun. On occasions, one of these pieces enters the Earth’s atmosphere. The friction it experiences while passing through the Earth’s atmosphere, at a speed of over 50 kilometres per second, causes it to burn up leaving a trail of white light...

The Constellations of Stars   Without the help of a telescope we can see about 6000 stars in the sky at night. Half of these can be seen in the northern sky and the other half in the southern sky. As we look at the stars we realise that we can form groups or shapes among them. These groups and shapes were mapped and classified by astronomers and given different names....

Galaxies in the Universe   It is estimated that the universe and its galaxies were formed some 15,000 million years ago due to a massive explosion. This theory of the astronomers is known as the ‘Big Bang Theory’. Since the ‘Big Bang’ the galaxies have been moving away from each other and the universe has been constantly expanding. Galaxies are large groups of stars, dust and gases, old stars are constantly...

The Milky Way The Milky Way is one of the many galaxies in the universe and the Sun is one of the 100 billion stars it has in it. The Milky way is so big in size that it takes light about 100 thousand years to travel from end to end. It tends to look patchy because in some parts of the galaxy the stars are closer to each other, as...

The Gaseous Planets     It is believed that all the planets were formed as a result of the combination of gases and clouds of dust about 4500 million years ago. Hydrogen is believed to have been found in the largest quantities in all planets, including the Sun. As time passed most of the smaller planets lost their reserves of hydrogen, largely because of their weak gravitational force. On the other...

The Sun As we look up in the night sky we see stars from end to end. Our Sun is no more than a star, It is our proximity to the Sun which makes it so bright and large in size. The Sun was born about 5000 million years ago as a result of the contraction of clouds of hydrogen, helium and dust into a ball under gravitational pressure. Very soon...

Jupiter the Largest Planet Jupiter is largely made of liquids, gases and swirling clouds of hydrogen and helium. These liquids and gases become denser and denser as we move towards the planet’s centre. Jupiter is the largest planet in the Solar system with a diameter of 1,42,884 kilometres, which is 318 times that of Earth. Besides this it is also the fastest spinning planet, it takes only 9 hours and 50...