Not so hot lightning
Lighting is supposed be three times hotter than the sun. Since the lighting
flashes are closer than the sun how come we don’t feel the heat when it flashes?
George
 Lightning pales beside the Sun as a heat source [NOAA and
SOHO]
Lightning can heat nearby air to 18,000 degrees Fahrenheit (10,000 C),
which is almost twice the
temperature of the Sun’s surface. Actually, the Sun’s surface isn’t so hot —
some welding torches are hotter. ( The Sun’s center, though, is 2500 times
hotter: 15 million degrees Celsius compared with 6 thousand degrees C.)
It isn’t the Sun’s temperature, however, that accounts for the
heat we feel on Earth. Rather, it’s her size. The Sun has a surface area a
hundred million billion times the surface area of a typical lightning bolt. We
receive only 1 billionth of the Sun’s energy. Even so, Earth gets much more
energy from the Sun than from a lightning bolt over the same time period — a
hundred million times more energy (calculation).
Close to the lightning strike can get blazing
hot. Lightning striking a tree can set it afire. The distance to the target,
however, must be small for us to feel the heat, because lightning’s radiant
energy pales compared with the Sun.
Further Reading:
Ball lightning: I
was wondering if Ball Lightning exists. What do you know about it? Where does
it happen? When and why?
Cause: What causes lightning?
Where it
hits: Where in the world do the most lightning strikes occur?
Ocean strikes: If lightning strikes the ocean, do the marine animals get
hurt or killed?
Kill and injure: How does lightning kill people and injure them? What
are the chances of being killed or injured?
Safe distance: What is the flash-to-bang time that's a safe distance from
lightning?
Safe
place: Where is a safe place to go during a thunderstorm?
Blue jet:
One night I was watching a storm and the lightning turned blue. How
did that happen?
How wide & long: My kids were wondering how wide and long lighting can be.
MountEverest: Does lightning strike Mount Everest?
What is lightning?, National Weather Service
HyperPhysics by Rod Nave: Heat radiation
HyperPhysics by Rod Nave: Lightning flashes and strokes
NOAA: What is
lightning?
(Answered July 9, 2004, updated July 19, 2007)
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