WatSen: Design and testing of a prototype mid-IR spectrometer and microscope package for Mars exploration

TL;DR

WatSen is a compact, rugged mid-IR spectrometer and microscope prototype designed for Mars exploration, capable of detecting silicates, carbonates, and water indicators under simulated Martian conditions.

Contribution

This paper presents the design, construction, and testing of a novel integrated mid-IR spectrometer and microscope package tailored for Mars surface analysis.

Findings

Successfully tested in Mars-like environment chamber

Achieved spectral resolution suitable for mineral detection

Produced high-resolution images of Martian soil analogs

Abstract

We have designed and built a compact breadboard prototype instrument called WatSen: a combined ATR mid-IR spectrometer, fixed-focus microscope, and humidity sensor. The instrument package is enclosed in a rugged cylindrical casing only 26mm in diameter. The functionality, reliability and performance of the instrument was tested in an environment chamber set up to resemble martian surface conditions. The effective wavelength range of the spectrometer is 6.2 - 10.3 micron with a resolution delta-wavelength/wavelength = 0.015. This allows detection of silicates and carbonates, including an indication of the presence of water (ice). Spectra of clusters of grains < 1mm across were acquired that are comparable with spectra of the same material obtained using a commercial system. The microscope focuses through the diamond ATR crystal. Colour images of the grains being spectroscopically analysed are obtainable with a resolution of ~ 20 micron.