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Text from: Star Flight Workbook (Published by Scott, Foresman & Company, USA)

A very large amount of electrical energy builds up in one spot in the atmosphere. What happens? Lightning flashes! While scientists are still trying to figure out why the energy builds up the way it does, they do know that lightning is just a giant electric spark. They also know that while a bolt of lightning may be no wider than a quarter of an inch, it may appear to be much wider because it makes the air around it glow. This is not surprising since a very powerful lightning bolt may be five times as hot as the sun!

While most lightning never reaches the ground, but bounces back and forth between the clouds, and while most of it that does reach earth does little or no damage, lightning can be dangerous. According to scientists' records, lightning has killed more people than hurricanes and tornadoes. And it can also damage houses, kill livestock, and cause forest fires.

An electronic machine was built for the United States Bureau of Land Management to help protect forests from fires started by lightning. A person monitoring the machine can spot and pinpoint lightning as far away as 250 miles. A patrol plane flies over the spot where lightning struck and, if a fire has started, firefighters are sent into the area to put it out.

You usually see a flash of lightning and then hear thunder a few seconds later. This is because light travels 186,000 miles a second and sound travels much more slowly-only 1,100 feet a second. To figure out how close the lightning is to you, count the number of seconds between seeing the flash and hearing the thunder. Multiply that number by 1,100. If you count five seconds, the lightning is 5,500 feet away or about a mile.

THINK & SEARCH  2.    If you saw a flash of lightning, and counted off 9 seconds, how far away was the lightning?  [2 marks]

AUTHOR & YOU   3.    After reading this article, you know a little about lightning. What is your opinion of lightning and the possible dangers it represents? Give reasons for what you say.  [3 marks]  »[Help]

ON MY OWN   4.    Based on your own experiences and what you have read, write an acrostic poem about lightning. Your word for the acrostic poem is "lightning".  [4 marks]