About every 75 years, a very special member of the solar system comes close to the Sun. it is Halley’s Comet, which is the brightest and most noticeable of all the comets that appear regularly. Do you know what a comet is? Comets are objects in space that are made up of gas, ice, dust, and small particles of rock. They travel around the Sun in an orbit. They are warmed up as they approach the Sun. this causes the comet to form a head and tail. The head is the cloud-like mass we see in the front. The tail is the trailing part which is made up of small particles and ice.
Halley’s Comet is named after Edmond Halley, who calculated its orbit. Though it was noticed by Chinese astronomers as early as 467 BC, it was Edmund Halley who recorded its appearance in 1682. The comet has appeared regularly every 75 to 76 years, in 1758, 1835, 1910 and 1986. Its last appearance was in 1986, and it is expected to appear next in 2061.
Shoemaker – Levy 9
In July 1994, the Shoemaker –Levy 9 comet broke apart and collided with Jupiter. This event gave astronomers a unique 
opportunity to observe what happens when such a collision occurs. The largest fragments were 2 kms in diameter, and struck Jupiter at a speed of around 60 km/s. the impact scars were clearly visible for months after the impact.
