THERMAP: a mid-infrared spectro-imager for space missions to small bodies in the inner solar system

TL;DR

THERMAP is a versatile mid-infrared spectro-imager designed for space missions to small solar system bodies, capable of thermal imaging and spectroscopy to analyze surface composition and temperature with high precision.

Contribution

It introduces a dual-channel instrument combining thermal imaging and spectroscopy using uncooled microbolometers for asteroid surface analysis.

Findings

Thermal images with temperature precision better than 3.5 K above 200 K.

Mid-infrared spectra with spectral resolution of 0.3 μm.

High signal-to-noise ratio spectra for temperatures above 350 K.

Abstract

We present THERMAP, a mid-infrared (8-16 {\mu}m) spectro-imager for space missions to small bodies in the inner solar system, developed in the framework of the MarcoPolo-R asteroid sample return mission. THERMAP is very well suited to characterize the surface thermal environment of a NEO and to map its surface composition. The instrument has two channels, one for imaging and one for spectroscopy: it is both a thermal camera with full 2D imaging capabilities and a slit spectrometer. THERMAP takes advantage of the recent technological developments of uncooled microbolometers detectors, sensitive in the mid-infrared spectral range. THERMAP can acquire thermal images (8-18 {\mu}m) of the surface and perform absolute temperature measurements with a precision better than 3.5 K above 200 K. THERMAP can acquire mid-infrared spectra (8-16 {\mu}m) of the surface with a spectral resolution {\Delta}{\lambda} of 0.3 {\mu}m. For surface temperatures above 350 K, spectra have a signal-to-noise ratio >60 in the spectral range 9-13 {\mu}m where most emission features occur.