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Name: Ashley
Status: student
Age: 12
Location: N/A
Country: N/A
Date: 1999 - 2000

Why do scientists rarely use miles or kilometers when measuring distance in space? what do they use? thank you please e-mail me back before Friday Oct. 6th :)

Scientists choose units of distance, time, and other physical measurements that correspond to a conveniently sized number. In the case of astronomy where objects are separated by great distances, it more convenient to use a light year, the distance light travels in one year.

At the other extreme, scientists may use nano-meters (=meters*10^ -9) because atomic/molecular distances range between tenths to hundreds of nanometers, so it is just simpler than carrying a lot of exponents of 10 around

Vince Calder

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