Global-scale Observations of the Limb and Disk (GOLD) Mission – Observing Forcing of the Thermosphere-Ionosphere System from Above and Below

The GOLD mission will provide unprecedented imaging of the Earth's space environment and its response to forcing from the Sun and the lower atmosphere. The mission will fly a far ultraviolet imaging spectrograph and is scheduled for launch into geostationary (GEO) orbit in October 2017 as a hosted payload on a commercial communications satellite flying over eastern South America. From this vantage point GOLD will repeatedly image the American hemisphere at a thirty-minute cadence. Fundamental parameters that will be derived from these measurements include composition (O/N2) and temperature of the neutral atmosphere on the dayside disk. Imaging of atmospheric composition, at only a daily cadence, has already provided many new insights into the behavior of the Thermosphere-Ionosphere (T-I) system. Combining composition with simultaneous temperature images will provide revolutionary insights into the behavior of the T-I system and its response to external forcing. Since GOLD will repeatedly observe the same geographic locations, it can distinguish between spatial and temporal variations in the T-I system caused by geomagnetic storms, variations in solar extreme ultraviolet radiation, and forcing from the lower atmosphere. GOLD's measurements and observing approach will give the scientific community a new understanding of the T-I system. In this presentation we will update GOLD's status and describe how simulations are being used to explore observing plans and to improve data products.