How Can Radio Telescopes Make Measurements of Small Objects?

Question: How do you use a dish type radio telescope to produce an image of something occupying such a small fragment of the sky?  — Martin

Answer: There are a couple of ways to make images of small objects using an array of radio telescopes.  You need to connect the radio telescopes so that they act like an array.  When radio telescopes make measurements together as an array, the resolution that the array can attain is determined by the largest distance between the individual antennas in the array.  So, if we can move telescopes in an array as far apart as possible, we can make very high spatial resolution measurements.  This is basically how we make high spatial resolution measurements of very small areas on the sky.  A nice description of how a radio telescope and a collection of radio telescopes functioning as an array can be found on the Square Kilometer Array web site.

Jeff Mangum