The Global Oscillation Network Group (GONG) is a community-based program to study solar internal structure and dynamics using helioseismology.
Six solar observatories are involved, with the intention of achieving almost unbroken observation of the Sun. The six observatories are the Teide Observatory (Canary Islands), the Learmonth Solar Observatory (Western Australia), the Big Bear Solar Observatory (California), the Mauna Loa Solar Observatory (Hawaii), the Udaipur Solar Observatory (India) and the Cerro Tololo Inter-American Observatory (Chile). In 2001, the original GONG detectors were upgraded to 1000 x 1000 pixels and continuous magnetograms were implemented, and the new system is known as GONG++. More recently (c. 2010), improvements to GONG observatory instrumentation have been made to enable imaging of the Hα ("H-alpha") spectral line of hydrogen in the solar atmosphere.
The GONG Program is managed by the National Solar Observatory, which is operated by AURA, Inc. under a cooperative agreement with the National Science Foundation