The next generation European Incoherent Scatter radar system upgrade (EISCAT_3D) is a single-sited international Research Infrastructure using radar observations and the incoherent scatter technique to study the atmosphere and the near-Earth space environment above the Fenno-Scandinavian Arctic as well as to support the solar system and radio astronomy sciences. The radar system is designed to investigate how the Earth’s atmosphere is coupled to space and the facility is almost fully dedicated to the solar-terrestrial physics, a research area where the interaction between the Sun and the Earth is studied. EISCAT_3D will also be suitable for other scientific targets and applications including climate change, space weather, plasma physics, space debris and near-Earth object studies.

The EISCAT Scientific Association was established in 1975 to conduct research on the lower, middle and upper atmosphere and ionosphere using the incoherent scatter radar technique. Since then, the facilities of the EISCAT have been continuously developed and extended and today comprise world-class radars and a powerful ionospheric heating facility. The EISCAT_3D system will consist of a phased-array radar system located in Northern Fenno-Scandinavia near space research centres in Kiruna (Sweden), Sodankylä (Finland) and Tromsø (Norway), two rocket launch facilities at Andøya (Norway) and Esrange (Sweden), and several other distributed instrument networks for geospace observation. In the ESFRI Roadmap since 2008, EISCAT_3D is expected to start operations at the end of 2022.