NASA/GSFC requires multiple models of CIMEL CE318-T Sun-Sky-Lunar Spectral Photometers, along with repair, maintenance, and upgrade parts, to support the AERONET program for monitoring aerosol optical properties. The contract will be a sole-source, Firm Fixed Price, Indefinite Delivery/Indefinite Quantity (IDIQ) award to CIMEL ELECTRONIQUE, with a five-year period of performance. No budget amount is specified. Performance location is not explicitly stated, but the work supports NASA’s global climate change and satellite validation programs. Interested parties may submit capabilities for competitive consideration by 4:00 PM EST on June 23, 2026.