GONG Program StatusFrank Hill & the GONG Team, National Solar Observatory, Tucson, AZ, USA

Potential field source-surface (PFSS) magnetic field models based on hourly synoptic maps are available in a variety of projections. Left to right: Synoptic Coronal Hole Plot; Line-Of-Sight Field Plot; Line-Of-Sight Ecliptic-Plane Field Plot .

The Future Of GONG: GONG has acquired substantial operational supportfrom AFWA to install and maintain an Hα observing capability as a backupfor the ISOON system. In addition, NSO is combining GONG and SOLIS intoa unified synoptic program, which will increase the efficient use ofavailable resources. We thus expect that GONG will continue to providedata to the community for at least another five years.

Samples of recent science in helioseismology: Top left: subsurface vorticity underflaring active regions. Top right: Far-side imaging. Lower left: Zonal velocity andtiming of the solar cycle. Lower right: Deep meridional flow. For more information,see the relevant posters.

Hα development: GONG is developing an Hα observing capability for the US AirForce Weather Agency (AFWA). The data will be used for space weather forecastingpurposes, and comprises 2k × 2k filtergrams obtained with a band pass of 0.4 Å.GONG will obtain Hα images at a peak cadence of 20 seconds. The images will bereturned and processed within one minute of acquisition. The Hα system will bedeployed by October 2010. Instruments are currently operating at Big Bear, Tenerife,and Learmonth.

FilterCCD Camera

Optics Light Baffle

The GONG Ha system: Top left: Image with limb darkening removed. Top right: Image enhanced with wavelet processing. Bottom: The instrument.

Magnetic field measurements: GONG provides continual line-of-sight 1k × 1kphotospheric magnetograms at a cadence of 60 seconds. Ten-minute averages andstandard deviations of the full-disk magnetic field are returned and made availablevia FTP shortly after acquisition. These magnetograms are combined into a synopticmap every hour, along with potential field source-surface extrapolations in a varietyof projections. The magnetograms are being used in the AFRL ADAPT program toproduce a forecast of the surface magnetic field of the sun, and as input to theAFRL/SWPC geomagnetic storm forecast based on the WSA and Enlil models of thesolar wind. The GONG magnetic field products are being continually refined toimprove the zero point (currently at 0.1 G), and to provide reliable estimates of thepolar fields. SOLIS synoptic map generation is now being incorporated into theGONG data processing system.

The average (left) and standard deviation (right) of a 10-min sequence of magnetograms. These products are returned in near-real-time.

A synoptic map constructed from approximately 4500 magnetograms. These maps are automatically updated every hour.

Introduction: GONG is celebrating its 15th anniversary this October, andhas recently produced a number of scientific advances, such therelationship of the torsional oscillation and the solar cycle; vorticitychanges below sunspots; improved far-side maps; and advances in thedetection of meridional flows throughout the convection zone. In addition,the capabilities of GONG have been expanded to include high-cadencefull-disk magnetograms and Hα intensity images. These additionalproducts are being used by several space weather research andoperational agencies and systems, including AFWA, SWPC, CCMC, CISM,and SWMF. With these recent developments, GONG is attractingadditional support, which should ensure that GONG continues to be aproductive asset for helioseismology and space weather.