scintillometry

Scintillometry is measurement of scintillation (with a scintillometer), e.g., the twinkling of stars as seen from Earth. Its measurement helps planning the location of telescopes and, at least in principle, provides input for adaptive optics systems.

In radio astronomy, scintillation caused by electron density variations in the interstellar medium (ISM), called interstellar scintillation (ISS), are relevant. The term diffractive interstellar scintillation (DISS) refers to a type of short-term effect and refractive interstellar scintillation (RISS) for a longer-term effect (though both are due to refraction effects of varying electron density). Weak scintillation (WISS or weak scattering) is another relatively weak type that occurs at lower frequencies. Radio scintillation of the interplanetary medium (IPM) (interplanetary scintillation or IPS) reveals information about the solar wind.

Measurement of scintillations produced by astronomical dust and gases can be used in observation, and distant, widely-spaced scintillation has been used as an interferometer on a very large scale, for viewing pulsars. In effect, this is using the ISM or interstellar plasma as a telescope.