Ionosphere

• Auroras

• Science: Earth Sciences: Atmospheric Sciences: Space Weather 

• High Frequency Active Auroral Research Program (HAARP)  - Devoted to the study of the properties and behavior of the ionosphere. Includes technical details about antenna design, data, and educational materials.
• JPL: Ionospheric and Atmospheric Remote Sensing  - Shares current data products measuring the ionosphere including maps and projections.
• SpaceWiki: Ionosphere  - Summarizes the ionosphere's composition, layers, and density changes.
• Super Dual Auroral Radar Network  - International radar network devoted to the study of the earth's atmosphere and ionosphere. Supported by the Johns Hopkins Applied Physics Laboratory.