NON SEQUITUR By: WILEY 2/18/1996
(c) 1996 Washington Post Writers Group
The most improperly used term from astronomy is the lightyear. A lightyear is NOT a measure of time but a measure of distance. It is the distance that light can travel in one year.
Light travels at 2.998*10^8 meters per second or Two hundred and ninety-nine million meters in one second. Therefore a lightminute is equal to 2.998*10^8*60, a lighthour is 2.998*10^8*60*60, a lightday is 2.998*10^8*60*60*24, and a lightyear is 2.998*10^8*60*60*24*365. Multiplied out a light year is 9.454*10^15 which written without scientific notation is:
This is Nine quadrillion Four hundred and fifty-four trillion meters. This equates to traveling around the Earth about 7 billion times!
How far can light travel in 1 nano-second? Well since we have the speed of light given above we can determine that in .000000001 seconds (1 nano-second) That light will travel .2998 meters. Since 1 meter is about 39.37 inches we can say that in 1 nano-second light will travel 11.8 inches, let's call it a foot!!
Therefore a light-foot is the distance light travels in 1 nano-second!!
On a clear night have you ever looked up into the heavens and wondered is there intelligent life out there ? . . .
Or are they just like us !!
SETI@HOME allows users to download freeware that looks at data 'chunks' received from the Arecibo telescope in Puerto Rico, this 'screensaver' program works when your computer is inactive and attempts to find any signs of intelligent life.
Below is an image of the Arecibo radio telescope (in Puerto Rico), the dish covers an area of about 20 acres.
A: Radio Continuum (0.4 GHz)
B: Atomic Hydrogen
C: Radio Continuum (2.7 GHz)
D: Molecular Hydrogen
F: Near Infrared
I: Gamma Ray
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