Studying for exam- telescope problem (help )

AI Thread Summary
To resolve a lunar lander measuring 3 meters across from Earth, the required diameter of an optical telescope can be calculated using the formula theta = 1.22 * lambda / d. A typical wavelength (lambda) in the visible spectrum should be assumed for the calculation. The angular separation (theta) can be determined by dividing the size of the lander by its distance from Earth, which is 3.8e8 meters. This approach provides a method to find the necessary telescope diameter for resolving the lander. The discussion emphasizes understanding angular separation in relation to telescope optics.
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studying for exam- telescope problem (help!)

Homework Statement



What diameter optical telescope on the Earth would you need to resolve a lunar lander 3 m across on the surface of the moon 3.8e8m away?

Homework Equations





The Attempt at a Solution


the only thing I can think of is to use theta=1.22lamda/d... but what do I do with it? help!
 
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You need to assume a typical value for lambda. A wavelength in the visible spectrum.
d is the diameter you need to calculate.
theta is the angular separation of two points that can just be resolved.
What is the angular separation of those two points on the moon?
 


oh! that makes sense. so is the angular separation the size of the lander divided by the distance to it?
 


That should work fine.

(Welcome to Physics Forums, by the way)
 


yay! thank you!
 

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