Lightning..


Oh yea.. very much that white thing followed by noise when the sky is black and usually raining or raining later.. that lightning :P

"Lightning is an atmospheric discharge of electricity accompanied by thunder, which typically occurs during thunderstorms, and sometimes during volcanic eruptions or dust storms. In the atmospheric electrical discharge, a leader of a bolt of lightning can travel at speeds of 60,000 m/s (130,000 mph), and can reach temperatures approaching 30,000 °C (54,000 °F), hot enough to fuse silica sand into glass channels known as fulgurites which are normally hollow and can extend some distance into the ground.

There are some 16 million lightning storms in the world every year."

phew.. that was something I must say...

Usually when its raining... I feel the heaven's leaking :D I believe the heavens leak when some of its very dear souls on Earth are upset.. the heaven weeps out for them... vanishing their sorrows and giving them light just like the one that comes after rain...and lightning.. its Hades being chasen by Zeus for me!!
But not for everyone...

Not long back someone asks me a simple question - Do you know how many thunderstorms are required to keep the Earth's atmosphere neutral?

Well being a science student I knew the Earth's atmosphere had a tendency to break to ions and get charged in the process... it was obvious that it would get to neutral else we all would have been electrified :P but I never thought beyond what I knew...

"An average bolt of negative lightning carries an electric current of 30 kiloamperes (kA), and transfers a charge of five coulombs and 500 MJ of energy. Large bolts of lightning can carry up to 120 kA and 350 coulombs. The voltage is proportional to the length of the bolt.
An average bolt of positive lightning carries an electric current of 300 kA or about 10 times that of negative lightning."

Taking '16 million' as an average number of light storms per year.. I am sure the complicated answer to the above simple question can be estimated!

Sometimes I wonder... is science the complicated way of dealing with beauty? I mean take this only as the example.. an amazing light amidst clouds turns to ionization of air and leakage of charge from clouds!! My God... till date humans have not resolved the mystery that no matter how many ever times you call the plumber.. the tap leaks! but we are so determined to find why clouds leak? How stupid!

"According to the electrostatic induction hypothesis charges are driven apart by as-yet uncertain processes. Charge separation appears to require strong updrafts which carry water droplets upward, supercooling them to between -10 and -20 °C. These collide with ice crystals to form a soft ice-water mixture called graupel. The collisions result in a slight positive charge being transferred to ice crystals, and a slight negative charge to the graupel. Updrafts drive the less heavy ice crystals upwards, causing the cloud top to accumulate increasing positive charge. Gravity causes the heavier negatively charged graupel to fall toward the middle and lower portions of the cloud, building up an increasing negative charge. Charge separation and accumulation continue until the electrical potential becomes sufficient to initiate a lightning discharge, which occurs when the distribution of positive and negative charges forms a sufficiently strong electric field.

The mechanism by which charge separation happens is still the subject of research. Another hypothesis is the polarization mechanism, which has two components:

1. Falling droplets of ice and rain become electrically polarized as they fall through the Earth's

natural electric field;
2. Colliding ice particles become charged by electrostatic induction"


Well.. here I think.. I have written and mentioned enough to get someone curious enough to find out more.. the others are getting a way lot bored with such talks!!

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