EISCAT (European Incoherent Scatter Scientific Association) is an international scientific radar association, which is specialised in the measurement of the atmosphere and the ionosphere, i.e. the top layer of the atmosphere. EISCAT provides data for use by space weather and plasma physics researchers. EISCAT aims to provide a sustainable and high-standard database on ionospheric measurements by developing and maintaining observation activities in cooperation with other ground station operators and operators performing satellite measurements. EISCAT systems are fully integrated in the global network of incoherent scatter radars.

EISCAT has radar antennas in Kiruna, Sweden, Sodankylä, Finland and Tromsø and Svalbard, Norway. The Tromsø research institute also has ionospheric thermal and short-wave radar. 

Seven countries are involved in EISCAT’s activities: Finland, Norway, Sweden, Germany, United Kingdom, China and Japan.