Radio Telescope at Arecibo, Puerto Rico

AI Thread Summary
The discussion centers on calculating the minimum resolution angle for the Arecibo radio telescope, which has a diameter of 295 meters and operates at a frequency of 300 MHz. The formula used is θ_min = 1.22(λ)/d, where λ is the wavelength calculated from the frequency. A participant initially miscalculated the wavelength and entered an incorrect answer in the wrong unit. Clarification was provided that the answer should be in milliradians (mrads), confirming that the unit conversion was necessary. The problem was ultimately resolved with the correct understanding of the units involved.
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Minimum Resolution Angle Problem

Homework Statement



The radio telescope at Arecibo, Puerto Rico, has a reflecting spherical bowl of 295 m diameter. Radio signals can be received and emitted at various frequencies with appropriate antennae at the focal point of the reflecting bowl. At a frequency of 300 MHz, what is the angle between two stars that can barely be resolved?

(The answer is supposed to be in mrads)

Homework Equations



(theta)min=1.22(lambda)/d

Lambda=(3.0E8)/(frequency)

The Attempt at a Solution



I tried converting the frequency to wavelength, and then plugging the wavelength, which I found to be 1m, and the given information into the first equation that I wrote down. The answer that I entered, .004136, wasn't correct, so I'm not sure if it's a wrong unit conversion, or I'm doing this wrong. First off, is the answer that I found in degrees? If it is, then would I need to convert it to radians? Secondly, what do they mean by mrads? Is it milli-radians?

Thank you.
 
Last edited:
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The answer will be in radians. Yes mrads means milliradians.
 
Solved it. Thank you Kurdt.
 
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