Tuesday, 23 May 2017

Angular resolution at Jodrell Bank

The cafe at Jodrell Bank is a good place to stop for refreshments on a long journey. You don't have to pay for the exhibition just to use the cafe and you get views like this! The dish has a diameter of 76.2 metres. Angular resolution is given by Rayleigh's Criterion and is wavelength/diameter. Frequencies are between 408 MHz and 6GHz. The respective wavelengths are 0.73 metres and 0.05 metres. This gives the respective angular resolutions as 0.00958 radians and 0.000656 radians, These are 0.55 degrees and 0.0376 degrees. This latter is 2.3 minutes of arc. Smaller is better for resolution: the smaller the angle the closer the two objects can be and still be distinguished.