The National Aeronautics and Space Administration (NASA) is seeking to procure a Replacement X-ray Detector for its Bruker M4 Tornado X-ray Fluorescence spectrometer, which is currently non-operational due to the failure of the existing detector. The new solid-state detector must meet specific technical requirements, including a large 60 mm² window, a resolution of less than 145 eV at 275,000 counts per second for manganese K-alpha, and detection limits for elements at the parts per million (ppm) level. This procurement is critical for maintaining operational capabilities in scientific research, particularly for projects related to the NASA Curiosity rover mission on Mars. Interested vendors must submit their capabilities and qualifications to the designated contacts by 11:59 a.m. Eastern Standard Time on April 25, 2025, to be considered for this sole source contract, which will be awarded to Bruker AXS LLC.