What Was the Resolving Power of Green Bank's 300-ft Telescope?

[sbarb25]

Question: Before it collapsed in 1989, Green Bank's 300-foot diameter telescope mapped the sky in H I. What was its resolving power?

I believe the formula you would use is resolving power = (wavelength in microns) / (diameter in meters)

So the diameter in meters would be about 91.44 m, but how do you know what the wavelength is? I guess I'm not sure what H I means...

Thanks for any help!

 

[NobodySpecial]

Assuming the Raleigh limit the diffraction limit (in radians) is something like 1.22 wavelength/diameter (assuming wavelength and diamter are in the same units)

H1 is the neutral hydrogen line, astronomers have funny nomenclature, H1 is un-ionized hydrogen, H2 is singly ionized (H+)

You can look up the wavelength and frequency easily ( google "neutral hydrogen line" )

 

[Chronos]

Dividing the dish diameter by wavelength gives you an idea of resolving power at any given wavelength.