Full-Disk Solar H Images from GONG › gallery › disk2k10 › data › 2011 › spd11 ›...
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Full-Disk Solar Hα Images from GONG J. Harvey, J. Bolding, R. Clark, D. Hauth, F. Hill, R. Kroll, G. Luis, N. Mills, T. Purdy (NSO), C. Henney (USAF AFRL), D. Holland (Cobham), J. Winter (Daystar Filters) Filter CCD Camera Lenses Light Baffle Beam Splitter Fold mirror Lens Filter CCD Camera Main Points • Full-disk Hα imaging added in mid-2010 to all six GONG sites • ~90% coverage at one image per minute • Backup for forthcoming ISOON network • Funded by U.S. Air Force Weather Agency • Data archived for research • Images available within a minute for real-time work The System • Separate, non-interfering addition to normal GONG helioseismology system • After preliminary processing, images are compressed and sent to a cloud server • Reduction is completed and images are normally available within a minute after exposure The Instrument • Uses GONG light feed and 7 cm objective lens • Polarizing beam splitter diverts otherwise unused 656 nm light through two afocalizing lenses • Daystar 0.04 nm passband mica etalon filter aperture matched to GONG entrance pupil • Following Galilean telescope forms a solar image on a DVC 2k x 2k interline CCD camera • Automatic adjustment of exposure time to keep quiet disk center at 20% of dynamic range • Image resolution limited by diffraction, seeing and high-order wavefront errors in the filters • Unique dual-heater system developed by Daystar to homogenize the passband properties Data and Access • In regular use for space weather forecasting by U.S. Air Force Weather Agency • Operational and reduction improvements underway • Archived data being used in research projects • Access at http://halpha.nso.edu . Main page shown to the right. Sample Observations • Below are sample images of various events extracted from archived data • Image scale is identical for all images (75 arc sec per inch) • Most images sharpened with a wavelet filter and saturated at ½ full range • Movies are available in the archive and at the gallery X-Class Flares M-Class Flares Post-Flare Loops Dark Prominence “Bubble” M Flare + Moreton Wave 2011 03 16 22h 2011 02 28 13h 2011 03 07 14h 2011 03 14 19h 2011 02 15 02h 2011 03 09 23h 2011 02 14 17h M-Class Flares with Surges 2011 04 22 16h 2011 04 22 05h 2011 04 15 17h 2011 03 24 18h 2010 08 07 18h 2011 02 16 14h 1 min running difference 2010 11 20 21h No filter, ¾ dynamic range 2011 03 16 23h
Transcript of Full-Disk Solar H Images from GONG › gallery › disk2k10 › data › 2011 › spd11 ›...
Full-Disk Solar Hα Images from GONGJ. Harvey, J. Bolding, R. Clark, D. Hauth, F. Hill, R. Kroll, G. Luis, N. Mills, T. Purdy (NSO),
C. Henney (USAF AFRL), D. Holland (Cobham), J. Winter (Daystar Filters)
FilterCCD Camera
Lenses Light Baffle
Beam Splitter
Fold mirror
Lens
Filter
CCD Camera
Main Points• Full-disk Hα imaging added in mid-2010 to all six GONG sites• ~90% coverage at one image per minute • Backup for forthcoming ISOON network• Funded by U.S. Air Force Weather Agency• Data archived for research • Images available within a minute for real-time work
The System• Separate, non-interfering addition to normal GONG helioseismology system• After preliminary processing, images are compressed and sent to a cloud server• Reduction is completed and images are normally available within a minute after exposure
The Instrument• Uses GONG light feed and 7 cm objective lens• Polarizing beam splitter diverts otherwise unused 656 nm light through two afocalizing lenses• Daystar 0.04 nm passband mica etalon filter aperture matched to GONG entrance pupil• Following Galilean telescope forms a solar image on a DVC 2k x 2k interline CCD camera• Automatic adjustment of exposure time to keep quiet disk center at 20% of dynamic range• Image resolution limited by diffraction, seeing and high-order wavefront errors in the filters• Unique dual-heater system developed by Daystar to homogenize the passband properties
Data and Access• In regular use for space weather forecasting by U.S. Air Force Weather Agency• Operational and reduction improvements underway• Archived data being used in research projects• Access at http://halpha.nso.edu. Main page shown to the right.
Sample Observations• Below are sample images of various events extracted from archived data• Image scale is identical for all images (75 arc sec per inch)• Most images sharpened with a wavelet filter and saturated at ½ full range• Movies are available in the archive and at the gallery
X-Class Flares M-Class Flares
Post-Flare Loops
Dark Prominence “Bubble”
M Flare + Moreton Wave
2011 03 16 22h
2011 02 28 13h
2011 03 07 14h
2011 03 14 19h
2011 02 15 02h
2011 03 09 23h
2011 02 14 17h
M-Class Flares with Surges
2011 04 22 16h
2011 04 22 05h
2011 04 15 17h 2011 03 24 18h
2010 08 07 18h
2011 02 16 14h
1 min running difference
2010 11 20 21h
No filter, ¾ dynamic range
2011 03 16 23h
