The goal of this Mid-Size Infrastructure (MSI) project is to build a mid-latitude extension of the SuperDARN High Frequency (HF) radar network. Radars in the international SuperDARN network measure important properties of Earth's ionosphere, including electric fields, plasma structures, and acoustic gravity waves. Progress in the study of Earth's near-space environment increasingly relies on the availability of these critical measurements on global scales. The interest in SuperDARN data products has spurred the recent development of a pair of polar cap radars by Canadian colleagues, extending SuperDARN capabilities to the highest latitudes. This MSI project, which is a collaborative effort involving four institutions, will result in eight new radars distributed over four sites situated along an arc extending from the Azores through the central United States to the Aleutian Island chain. The new radars will provide unprecedented views of the dynamics of the subauroral ionosphere and inner magnetosphere. The feasibility of such measurements at middle latitudes has been demonstrated with the deployments of single, isolated SuperDARN radars in the eastern United States (Wallops Island, Blackstone) and in Japan (Hokkaido). The existing radars will be operationally folded into the MSI chain. The realization of this large-scale and long-term observational capability will furnish the space physics community with new infrastructure and a valuable tool for engaging students in cutting-edge research. SuperDARN data collected from high latitudes are used by space scientists all over the world. The existing radar network was developed incrementally over 15 years with the steady addition of international partners. This project will initiate the acquisition of comparable infrastructure at mid-latitudes thereby taking advantage of recent developments at polar latitudes and the existing high-latitude SuperDARN network to provide expanded coverage of effects in the magnetosphere, ionosphere, and neutral atmosphere. The protocols and distribution methods currently used for SuperDARN data and data products will be utilized to ensure the same ease of access to data. As occurred with high latitude SuperDARN, international partners are simultaneously seeking funds to build complementary radars in Europe and Asia. The participants in this project are all associated with institutions of higher learning and view the infrastructure as both a teaching and research investment. Data from the high-latitude SuperDARN radars have contributed to numerous advanced degrees and the mid-latitude extension will furnish many more opportunities. Students at the collaborating institutions will be heavily engaged in the work of this project both at their home institutions and at the individual radar sites. Measurements provided by the infrastructure will enable transformational science and support research across a broad range of topics in the physics of the magnetosphere, ionosphere, and upper atmosphere. At the same time, this effort will: (1) provide the research community with extensive mid-latitude ionospheric and atmospheric datasets; (2) provide large-scale context for ongoing and future spacecraft and rocket missions; (3) generate new research possibilities in space science for students; (4) provide opportunities for students at U.S. universities to gain hands-on experience with radar technology and in the management of a major scientific collaboration. All data and data products will be made freely available through the SuperDARN website.
