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Q3.
The Ring Nebula has an angular
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diameter
of 72 arcsec, and we estimate it is
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5000
light years away. What is its linear
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diameter?
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Linear
diameter = 5000 ly x 72/206265
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Linear
diameter = 1.7 light years
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An
aside. Exansion rate is 15 km/s, so
the age is
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approximately
34,000 years old.
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