White Light Photosphere Observed from ISOON

The Air Force Research Laboratory's Space Hazards Branch, in partnership with the National Solar Observatory at Sacramento Peak, developed a prototype instrumentation and software for the Improved Solar Observing Optical Network (ISOON). ISOON was to have replaced the existing SOON system which was originally designed and deployed in the 1970's for space weather specifications and forcasting. As envisioned, ISOON was to have featured autonomous, rapid-cadence solar imaging spectroscopy and imaging spectropolarimetry at four sites around the world, while transmitting solar images in near-real time to central analysis facilities at Air Force Space Command and NOAA/SEC (now SWPC). The ISOON technical approach was to retain the front end of the existing SOON telescope but replace the optical bench, birefrigent, and spectrograph with a dual Fabry-Perot filter system, CCD array detector, and secondary optics contained in a pod behind the main telescope tube. Planned ISOON products included full-sun images (on 1-arcsecond pixels) in H-alpha (acquired 1 per minute), and line-of-sight magnetic field (1 per 3 hours), as well as parametrized data such a flare brightness, location, area, and times of onset and maximum. Following its development and prior to its deployment the USAF cancelled the ISOON program. The current dataset available from NOAA/NCEI includes image from the protoype ISOON system at Sacramento Peak from 2003 to 2012.