Global-scale Observations of the Limb and Disk

Global-scale Observations of the Limb and Disk, or GOLD, is a NASA mission of opportunity that measures densities and temperatures in Earth’s thermosphere and ionosphere. GOLD makes these measurements, in unprecedented detail, with an ultraviolet (UV) imaging spectrograph on a geostationary satellite.

The goal of the investigation is to provide answers to key elements of an overarching question for Heliophysics science: What is the global-scale response of the thermosphere and ionosphere to forcing in the integrated Sun-Earth system?

The measurements from GOLD will be used, in conjunction with advanced models of the thermosphere and ionosphere, to revolutionize our understanding of the space environment.

ICON vs. GOLD infographic (5 MB PDF)

GOLD fact sheet (4 MB PDF)

GOLD postcard – 6″ x 9″ (5 MB PDF)


GOLD Reveals Unexpected Changes in Earth’s Nighttime Ionosphere






Earth’s Shining Upper Atmosphere—From the Apollo Era to the Present






First Release of Data from GOLD






The GOLD mission launched at 5:20 p.m. EST, Thursday, Jan. 25, as a commercially hosted payload on the SES-14 satellite. The satellite was launched on an Ariane-5 rocket from the Guiana Space Centre in Kourou, French Guiana.

Read the latest launch status update.