(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Estimate the radius of a spherical HII region which rests at a distance of 500 pc that subtends an angle of 20' at the observer. [1'=3x10-4 radians]

2. Relevant equations

L=D(theta)

Where D is the distance, L is the angular size and theta is the angle.

3. The attempt at a solution

L= 500*20*3*10^-4 = 3pc

L=3pc

Radius = 1.5 pc

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# Homework Help: Calculating the radius of a HII region - worked out but just need you to check!

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