The Global-Scale Observations of the Limb and Disk (GOLD) Mission

Monday, August 14, 2017

The NASA Global-scale Observations of the Limb and Disk (GOLD) mission is a dual-channel imaging spectrograph that will be carried on a commercial communications satellite in geostationary orbit. Launch is scheduled for January, 2018.

GOLD atomic oxygen emissions image
Left: Simulation of GOLD atomic oxygen emissions at 135.6 nm, calculated using atmospheric densities from the NCAR Thermosphere-Ionosphere-Electrodynamics General Circulation Model and radiances from the Global Airglow model. An example location of the spectrograph entrance slit as it scans across the disk is superimposed as a white line. Right: Model spectral image at that slit location, including the atomic oxygen emission lines and molecular nitrogen Lyman-Birge-Hopfield bands.

GOLD will measure ultraviolet emissions from the Earth in the wavelength range 132 to 162 nm, and deduce two critical variables, thermospheric temperature and the ratio of atomic-to-molecular composition, on the dayside disk at about 160 km altitude. At night, GOLD will observe the evolution of the low latitude ionosphere and the formation of plasma depletions. This paper, written by Principal Investigator Richard Eastes and the GOLD science team, provides an overview of the instrument, the scientific objectives, the observing strategy, retrieval algorithms, and data products.

Space Science Reviews, 2017, doi:10.1007/s11214-017-0392-2, by Richard W. Eastes et al. (HAO co-authors: Alan Burns, Art Richmond, and Stan Solomon.)