On Sept. 9, 2021, a sounding rocket launched from the White Sands Missile Range in New Mexico, carrying a copy of the Extreme Ultraviolet Variability Experiment, or EVE. This flight was used to calibrate the identical version of EVE that has flown in space since 2010 aboard NASA’s Solar Dynamics Observatory (SDO). Over the years, the space-based EVE has become degraded by intense sunlight, so scientists fly periodic calibration missions to keep EVE’s measurements sharp.
GCMD keywords can be found on the Internet with the following citation:
Olsen, L.M., G. Major, K. Shein, J. Scialdone, S. Ritz, T. Stevens, M. Morahan, A. Aleman, R. Vogel, S. Leicester, H. Weir, M. Meaux, S. Grebas, C.Solomon, M. Holland, T. Northcutt, R. A. Restrepo, R. Bilodeau, 2013. NASA/Global Change Master Directory (GCMD) Earth Science Keywords. Version 8.0.0.0.0