Riddle on Astronomy - What Heavenly Body has a Head and a Tail?
Riddle - What Heavenly Body has a Head and a Tail?
Answer to the Riddle: A Comet.
Comets are bright objects with long tails, which we sometimes see streaking across the night sky. The head, the main part, is probably made of frozen water, frozen ammonia, dry ice, pieces of stone and metal, and dust. It is somewhat like a big dirty snowball that shines because it reflects sunlight. As it comes near the sun, it ices turn to vapour forming a tail of gases. Great Comet of 1843 has the longest tail which stretched over 800 million km. Some comets are bright enough to be seen with the naked eye, while others can only be seen with the aid of a telescope.
The most famous and ancient comet 'Halley Comet' is named after the British Scientist Edmund Halley (1656-1742). He accurately predicted that this particular comet would be seen in the night sky in 1758. He was the first person to predict when a comet would arrive. Halley's Comet orbits the Sun every 76 years. It was last seen in 1986 and its next vist will be in 2062.
Comets - Orbital Periods of Comets
The orbital periods of Comets range from a few to hundreds of years. Here is some of the famous comets and its orbital periods.