So we were taking measurements for an experiment in our radio astronomy lab. For the first part of the experiment, we recorded the intensity of a far away point source ( the signal from a TV satellite was used for the point source ) detected by commercial satellite dish and receiver. When we plotted the intensity against the angle ( we traversed the dish across the satellite, so the curve we had was a 1D cross section of the 2D intensity distribution ), it looked like a Gaussian (http://en.wikipedia.org/wiki/Gaussian_function ). I was actually able to fit a Gaussian to it. But then I read about what we were supposed to get, and found that we were supposed to get an Airy disk from a point source ( http://en.wikipedia.org/wiki/Airy_disk ). So I'm curious. How close is an Airy disk to a Gaussian? Can I get a Gaussian from an Airy disk by making some parameter close to zero or infinty or something? Thanks.