The Global Oscillation Network Group (GONG) is a community-based program to study solar

Sun

The Sun is the star at the center of the Solar System. It is almost perfectly spherical and consists of hot plasma interwoven with magnetic fields...

 internal structure and dynamics using helioseismology

Helioseismology

Helioseismology is the study of the propagation of wave oscillations, particularly acoustic pressure waves, in the Sun. Unlike seismic waves on Earth, solar waves have practically no shear component . Solar pressure waves are believed to be generated by the turbulence in the convection zone near...

.

Six solar observatories are involved, with the intention of achieving almost unbroken observation of the Sun. The six observatories are the Teide Observatory

Teide Observatory

The Observatorio del Teide is an astronomical observatory on Tenerife operated by the Instituto de Astrofísica de Canarias. Opened in 1964, it became one of the first major international observatories, attracting telescopes from different countries around the world because of the good astronomical...

 (Canary Islands

Canary Islands

The Canary Islands , also known as the Canaries , is a Spanish archipelago located just off the northwest coast of mainland Africa, 100 km west of the border between Morocco and the Western Sahara. The Canaries are a Spanish autonomous community and an outermost region of the European Union...

), the Learmonth Solar Observatory (Western Australia

Western Australia

Western Australia is a state of Australia, occupying the entire western third of the Australian continent. It is bounded by the Indian Ocean to the north and west, the Great Australian Bight and Indian Ocean to the south, the Northern Territory to the north-east and South Australia to the south-east...

), the Big Bear Solar Observatory

Big Bear Solar Observatory

The Big Bear Solar Observatory is an astronomical telescopic observatory with main interests in studying the physics of the Sun. The instruments and telescopes of the observatory are designed and employed specifically for studying the activities and phenomena of our solar system's star...

 (California

California

California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...

), the Mauna Loa Solar Observatory

Mauna Loa Solar Observatory

The Mauna Loa Solar Observatory is a collection of instruments for observing the sun located on the slopes of the Mauna Loa volcano on the island of Hawaii, USA at an elevation of .-General information:...

 (Hawaii

Hawaii

Hawaii is the newest of the 50 U.S. states , and is the only U.S. state made up entirely of islands. It is the northernmost island group in Polynesia, occupying most of an archipelago in the central Pacific Ocean, southwest of the continental United States, southeast of Japan, and northeast of...

), the Udaipur Solar Observatory

Udaipur Solar Observatory

The Udaipur Solar Observatory is in Udaipur, Rajasthan in India on an island in the Fateh Sagar Lake. The sky conditions at Udaipur are quite favourable for solar observations. Since the observatory is situated amidst a large mass of water, air turbulence which occurs due to ground heating by...

 (India

India

India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...

) and the Cerro Tololo Inter-American Observatory

Cerro Tololo Inter-American Observatory

The Cerro Tololo Inter-American Observatory is a complex of astronomical telescopes and instruments located at 30.169 S, 70.804 W, approximately 80 km to the East of La Serena, Chile at an altitude of 2200 metres. The complex is part of the National Optical Astronomy Observatory along with Kitt...

 (Chile

Chile

Chile ,officially the Republic of Chile , is a country in South America occupying a long, narrow coastal strip between the Andes mountains to the east and the Pacific Ocean to the west. It borders Peru to the north, Bolivia to the northeast, Argentina to the east, and the Drake Passage in the far...

). In 2001, the original GONG detectors were upgraded to 1000 x 1000 pixels and continuous magnetograms

Magnetogram

The term magnetogram has two meanings, used separately in the contexts of magnetic fields of the Sun and the Earth.In the context of the magnetic field of the Sun, the term magnetogram refers to a pictorial representation of the spatial variations in strength of the solar magnetic field...

 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

H-alpha is a specific red visible spectral line created by hydrogen with a wavelength of 656.28 nm, which occurs when a hydrogen electron falls from its third to second lowest energy level...

 ("H-alpha") spectral line of hydrogen

Hydrogen

Hydrogen is the chemical element with atomic number 1. It is represented by the symbol H. With an average atomic weight of , hydrogen is the lightest and most abundant chemical element, constituting roughly 75% of the Universe's chemical elemental mass. Stars in the main sequence are mainly...

 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

External links

• GONG info at the National Solar Observatory
  National Solar Observatory
  The mission of the National Solar Observatory is to advance knowledge of the Sun, both as an astronomical object and as the dominant external influence on Earth, by providing forefront observational opportunities to the research community...
  
  site