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Light year question?

  • Thread starter roxxyroxx
  • Start date
1. Homework Statement
If a star explodes 30 light years from the earth when will we be able to see it?


2. Homework Equations

one light year = 9.47 x 1012km
speed of light = 3.00 x 108m/s

3. The Attempt at a Solution
the answer in my workbook says 30a but idk what the value of a is
 
The definition of light year tells us that light will take 30 years to travel that distance, so the answer is indeed 30 years.
 

Astronuc

Staff Emeritus
Science Advisor
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a could be an abbreviation for annum (year) or anni (years).
 

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