Global-scale observations of the limb and disk mission implementation: 2. Observations, data pipeline, and level 1 data products

GOLD employs two identical ultraviolet spectrographs that make observations of the Earth's thermosphere and ionosphere from a commercial communications satellite owned and operated by Societe Europeenne des Satellites (SES) and located in geostationary orbit at 47.5 degrees west longitude (near the mouth of the Amazon River).

They make images of atomic oxygen 135.6 nm and N-2 Lyman-Birge-Hopfield radiances from the entire disk that is observable from geostationary orbit and on the near-equatorial limb. They also observe occultations of stars to measure molecular oxygen column densities on the limb. Here we describe the algorithms and science data processing that convert downlinked data to spectral-spatial image cubes and occultation spectra, calibrated in geophysical units.