The Enfys Spectrometer for the ExoMars Rosalind Franklin rover

A main goal of the ExoMars Rosalind Franklin Rover (EMRF) mission is to search for past life on Mars, preserved within phyllosilicate-bearing geological deposits at its landing site in Oxia Planum. Enfys is a new infrared spectrometer added to the mission payload in 2023 and is currently under development for Flight Model delivery in 2026 and launch in 2028 for landing in 2030. Enfys will provide remote sensing spectroscopic capabilities for exploration, target selection, and geological contextualisation through the measurement of point infrared reflectance spectra. Enfys will play a major role not only in mission operations, but also in linking orbital and in situ spectroscopic observations and mineralogical interpretations. As a replacement for the former Roscosmos ISEM instrument, Enfys has been developed at pace to meet the revised mission schedule, drawing heritage from the Panoramic Camera (PanCam), an instrument Enfys will work in concert with. In a little under 3 years since inception, the first Enfys prototype has now been assembled, characterised and calibrated, for installation on the Amalia Ground Test Model rover.

Enfys utilises two near-infrared Linear Variable Filters (LVFs), each with a dedicated InGaAs detector. Together, these cover the wavelength range 0.9 – 2.5 mm. Both LVFs are translated simultaneously on a mechanical stage. Enfys sits on top of the EMRF mast, co-aligned with and directly underneath the High Resolution Camera (HRC) element of the PanCam instrument. Embedded within the design is an overlap in wavelength range with PanCam covering 0.9 and 1 mm, allowing spectral continuity between VIS-NIR multispectral imaging and point IR spectroscopy. Enfys data will also be complementary to the other near-infrared spectrometers on EMRF, including Ma-MISS, which will collect data from within the drill hole, and MicrOmega, which will analyze the drill core once collected, prepared and delivered into the analytical suite inside EMRF. To maximise the scientific return from Enfys, a variety of geological analogue testing is currently underway with Enfys emulators. This has focused on sedimentary deposits, ranging from mudstones to sandstones of compositions ranging from mafic to felsic, and ages from 2.7Ga to 10Ka. An overview of the Enfys project will be presented, along with instrument design and performance figures and analogue study results.