Planetary Instrument for X-ray Lithochemistry

  • PIXL Xray head
    PIXL X-ray Head including the 30 kV High Voltage Module


Mission: Measuring the chemical makeup of rocks at a minute scale, specifically seeking signs of microbial life in Martian soil.

Challenge: Trace numerous chemicals at just a few parts per million concentration while keeping the instrument smaller and more compact than any comparable lab tool.

Solution: Microfocus X-ray fluorescence (XRF) instrument and high-resolution imager.

Value: PIXL makes use of XRF to measure 26 different elements at submillimeter levels– lower concentrations than any previous scientific instrument in a Mars mission payload. Its acuity and data acquisition speed makes the instrument extremely versatile– a necessity for adapting to the multiple scientific opportunities and unforeseen obstacles that may arise on the Mars 2020 mission.

Key PIXL Technology

  • X-ray spectrometer
  • Polycapillary optics to focus X-rays 
  • Optical fiducial system (OFS)
  • Color Micro-Context Camera (MCC)
  • LED illuminator 
  • high-voltage power supply (HVPS)
  • Instrument data processing “Adaptive Sampling”

Lab: SPRL in cooperation with NASA

Scientific Objective

Is there life on Mars? This is a question that has captured human imaginations for decades, and is the root of NASA’s ongoing efforts in robotic exploration on the Red Planet. Measuring the chemistry of rocks is one of the fundamental tools for geological and astrobiological exploration of rocky planets. 

PIXL is one of several instruments that will aid in NASA’s Mars 2020 rover mission endeavoring to find signs of both habitable conditions and past microbial life in Mars’ geological history. PIXL makes use of microfocus X-ray fluorescence to rapidly measure elemental chemistry in sediments. In providing detailed geochemical assessments of past environments, PIXL aids the larger goal of collecting data for characterizing Martian geology and preparing for future human exploration of this neighboring planet.