High-temperature pressure sensors have myriad potential applications. These include down-bore sensor packages for exploratory, oil and gas, and geothermal drilling, coal and biomass gasification, power generation, and a wide variety of biofuel and petrochemical refining processes. In addition to allowing for direct pressure measurement in ultra-high temperature processes without requiring undesirable compromises, the Eltron pressure sensor will also function as a drop-in replacement for existing pressure transducers. In-situ resource utilization and extraterrestrial resource extraction are essential aspects of many near- and long-term NASA mission. Many technologies like oxygen extraction from Lunar Regolith and Martian soils can develop very high temperatures. Existing pressure sensors are not capable of operating continually at temperatures in excess of about 550 deg. C. During this research, Eltron will develop a new ultra-high temperature piezoresistive pressure sensor capable of continuous operation between 5501200 deg. C. In addition, the proposed sensor design incorporates only vacuum compatible materials and will not be impacted by operation in microgravity or reduced pressure atmospheres.