They get that resolution by having a radio telescope array with many sensors spread over a wide area [0]. An incoming wavefront will hit the different sensors a

They get that resolution by having a radio telescope array with many sensors spread over a wide area [0]. An incoming wavefront will hit the different sensors at slightly different times, depending on the direction the wave is coming from. By combining all the sensors' data, you can calculate the intensity of incoming radiation from every direction in the sky. The resolution increases as you increase the horizontal distance between the sensors, because that makes it easier to resolve the arrival time differences. [0] https://en.wikipedia.org/wiki/Australian_Square_Kilometre_Array_Pathfinder#/media/File:CSIRO_ScienceImage_2161_Close_up_of_a_radio_astronomy_telescope_with_several_more_in_the_background.jpg https://en.wikipedia.org/wiki/Australian_Square_Kilometre_Ar...