Interferometer – The term “interferometer” refers to an instrument that has either two optical inputs (e.g., a periscopic system) or two radiation receivers that are spaced as far apart as possible. By matching the phase difference of the electromagnetic radiation that arrives at them, a higher resolving power than any telescope can be obtained. In fact, it is greater than the distance between the optical inputs or receivers of radiation, which is called the base of the interferometer. With optical interferometers, a base of 15 meters can be achieved.
This gives a resolution of up to 0.001 angular seconds, allowing accurate measurement of the linear dimensions of the most distant stars. In addition, there is the Keck telescope. Let us assume that in the case of radio interferometers, the base can be larger than the diameter of the Earth if the two antennas are mounted on different spacecraft. At the same time, the resolution could be as high as 0.00003 arc second.
