In 1995, GONG started its operations as a 3-year project aimed at investigating the internal structure and dynamical behavior of the Sun through the analysis of solar oscillations (so called, helioseismology). Over the years, GONG observations were used by several generations of scientists to study the parameters of the acoustic modes, and their variations over time and space. Accurate knowledge of variability of these parameters within the solar interior is essential for understanding the origins of magnetic activity and for constraining solar dynamo models. One of the early results of helioseismology using GONG data was the determination of the internal profile of the solar rotation rate as a function of depth. In particular, the sharp transition from differential to solid-body rotation, termed the tachocline, was discovered at the base of the convection zone (about 200,000 km below solar visible surface). Later, a thin shear layer in the rotation rate immediately below the solar surface was detected. The latter is referred to as the Near-Surface Shear Layer (NSSL), or leptocline.
While the line-of-sight (LOS) magnetograms were produced by GONG from the beginning of the project, it was not until 2001, when the magnetograms from the upgraded GONG++ saw the extensive use for studying magnetic properties of the Sun, their changes with the flare activity, solar cycle, modeling of coronal and interplanetary magnetic field, and solar wind. In 2010, GONG was also upgraded to take observations in hydrogen H-alpha spectral line.
GONG data continue to be extensively used by the research communities both in U.S. and abroad. See this post for highlights of scientific discoveries and early GONG history. The data are now used operationally by the National Oceanic and Atmospheric Administration (NOAA) Space Weather Prediction Center (SWPC), the space weather prediction center of U.K. MetOffice, and in other countries (e.g. Japan, South Korea). For space weather awareness, GONG data are included in the analyses of NASA’s Moon-to-Mars office. GONG observations are downloaded for modeling of solar wind and solar eruptive events by the US university groups, research organizations in Europe, and Community Coordinated Modeling Center (CCMC) operated by NASA. Data is used for predicting the magnetic connectivity between the solar surface and NASA’s Parker Solar Probe (PSP) during its closest (perihelia) approach to the Sun. Farside images derived from GONG data are used for predicting future sunspot activity on Earth, and the appearance of sunspots on farside when observed from the EU's Solar Orbiter, or from a rover on Mars surface.
GONG observations are also used widely by amateur astronomers to provide a reference and overall guidance for their observations. “The GONG Show” depicting H-alpha and white light images are posted regularly on the amateur astronomy website at https://www.cloudynights.com/. As one example, we show image reproduced from Sun Ha Session, 2026-04-29 (Frank Lothar Unger) - AstroBin that uses GONG full disk image as a reference.
GONG data has been incorporated into several apps both for scientific research communities and for public. This includes the Solar-MACH, a web-tool widely used in the heliospheric community. It obtains, among others, GONG magnetograms using sunpy's fido functionality to use them for the Potential Field Source Surface (PFSS) modelling. The Solmate (solmate.nz), a space weather dashboard for New Zealand, employs a Filament Tracker to highlight filaments on GONG full-disk H-alpha images and watch for eruptions that might send a CME towards Earth. In Australia, an amateur astronomer is working on a project that incorporates GONG H-alpha full-disk images in his star atlas application. Recently, FaktPocasi.cz, a free Czech weather and space-weather website contacted GONG project about their plans to display current GONG observations on their site with additional explanations in plain language of what is happening on the Sun.
Currently, two public competitions are using GONG observations. One is hosted by the Frontier Development Lab (FDL) https://fdl.ai/benchlab-solar-wind-prediction-2026, and is concentrated on prediction of solar wind using magnetograms from different instruments including GONG. The other, Kaggle competition "Solar Filament Segmentation Challenge 2026" is one of seven IEEE Big Data Cup 2026 Data Challenges at the Frontier of AI, Science & Society, https://bigdataieee.org/BigData2026/cup/. It aims at the proper segmentation of solar chromospheric filaments using GONG H-alpha images.
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