I have two stars that are separated by an angle of 3x10^5 radians. They are both emitting monochromatic light on 600nm. I would like to find the diameter of the smallest telescope that can resolve the two stars.(adsbygoogle = window.adsbygoogle || []).push({});

For the angular limit of resolution I have

[tex]

\Delta \theta = \frac{1.22 \lambda}{D}

[/tex]

Where D is the diameter of the lens.

Rearranging I get

[tex]

D = \frac{1.22 \lambda}{\Delta\theta}=\frac{1.22*600*10^{-9}}{3*10^{-5}} = 2.44 cm

[/tex]

I'm quite sure that the answer is 2.5 cm. Where am I going wrong? Where does the 1.22 come from?

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# Homework Help: Resolviong two images?

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