New developments in sunphotometry, left, prototype SEASTAR (SEAgoing Sky-scanning, sun-Tracking Atmospheric research Radiometer) for ship-based deployment of sunphotometers, center, 4STAR-B (Spectrometers for Sky-Scanning Sun Tracking Atmospheric Research - B), right, ground prototype with newly developped multi-decade radiometers for 5STAR (ultra-Stable Spectrometers for Sky-Scanning Sun Tracking Atmospheric Research), far right, Dr. Steve Broccardo, NASA Post-doctoral Program Fellow.