Parsecs In astronomy the light year (abbreviated ly) and the parsec (abbreviated pc) are t...

Parsecs In astronomy the light year (abbreviated ly) and the parsec (abbreviated pc) are the two units used to measure distances. The distance in space at which a line from the earth to the sun subtends an angle of 1 sec is 1 parsec. Find the number of miles in 1 parsec by using a right triangle positioned in space with its right angle at the sun as shown in the figure. Use scientific notation and one decimal place. How many years (to the nearest hundredth) does it take light to travel 1 parsec? (One light year is the distance that light travels in one year, one AU is the distance from the earth to the sun, and 1 ly = 63,240 AU.)

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