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Introducction JAXA’s MMX (Martian Moons eXploration) mission, to be launched in 2024, will study both Martian satellites, for several years, and will drop a small rover to Phobos, to explore its surface [1]. As part of this rover scientific payload, it will be placed a Raman spectrometer, the RAX Instrument (Raman Spectrometer for MMX). The RAX will be able to analyse the mineral composition of the Phobos regolithe surface with in-situ measurements, complementing the Japanese Sample Return mission, and helping to reveal the nature and distribution of materials on the Martian Moon’s surface, and ultimately its origin and evolution [2]. The RAX instrument [3] has been designed, manufactured, integrated and tested by an international consortium led by DLR (Germany), with significant contributions from JAXA & University of Tokyo (Japan), and INTA-CAB-UVa (Spain). One of the Spanish contributions to RAX, will be the instrument Verification Target, a small piece of PET (polyethylene terephthalate) attached to MMX spacecraft, to be used before launch, and during cruise; for spectral instrument performances verification on-ground and just before the rover release to Phobos. Figure 1. RAX Verification Target design proposed by INTA-CAB-UVa Experimental Thanks to previous expertise of the UVa-INTA group with PET material, used on the Raman Laser Spectrometer (RLS) Calibration Target [4] for ESA’s ExoMars mission; and SuperCam Calibration Target [5] for NASA Mars2020; a newly design-deuterated PET material, decreasing the PET fluorescence background, and adding new Raman bands with respect to ordinary PET [6] has been developed, manufactured, characterized and space-qualified for MMX-RAX mission by INTA-CAB-UVa; so it was proposed as candidate the RAX Verification Target. Figure 2. RAX Verification Target Flight batch for qualification/acceptance Results and discussion During the session, a detailed description of different tests carried out for the space qualification of the deuterated material, will be shown. And how the final performances with respect to other commercial PETs have been improved; and so, how the final verification-calibration of the Raman instrument has been optimized. Acknowledgements INTA’s internal I+D+I project IDMats; and MICINN grants PID2019-107442RB-C32 & PID2019-107442RB-C31 References [1] Michel P. et al. (2022) Earth, Planets and Space 74, 2. [2] Hagelschuer, T. et al. (2019) 70th Int. Astronautical Congress, 2019. [3] Hagelschuer, T. et al. (2022) 73th Int. Astronautical Congress. [4] López-Reyes, G. et al. (2020) Journal of Raman Spectroscopy, 1-13 [5] Manrique, J.A. et al. (2020) Space Sci Rev, 216:138 [6] Mora, J. et al (2020) Acta Astronaut. 167 (2020) 360–373

Introduction. Understanding the origin and evolution of Phobos and Deimos is the goal of the coming Martian Moons eXploration mission (MMX) led by JAXA [1, 2, 3]. This mission will be launched in 2024 to the Martian system and return samples from Phobos. Before sample return operations, a rover of 25 kg approximately will be delivered to the surface carrying four instruments: a Raman spectrometer (RAX), a radiometer (miniRad), a stereo pair of cameras looking forwards (NavCams), and two cameras looking at the wheel-surface interface, (WheelCams) [4]. The RAX instrument. The RAman spectrometer for MMX, RAX, has been developed together by DLR, INTA/UVA, and JAXA/UTo [5]. It consists of three elements: I) The RAX Laser Assembly (RLA), which was originally designed for the RLS instrument of the ExoMars mission, and includes a laser emitting at 532 nm; II) The RAX Spectrometer Module (RSM), comprising a sophisticated confocal optical assembly and a CMOS detector that covers a spectral range of up to 4000 cm-1 with a spectral resolution of ̴ 10 cm-1; III) The Autofocus System (AFS) to measure with high precision at different positions onto the ground. RAX will in situ examine the minerals of the surface and their formation conditions at rover sampling spots. By analysing the vibrational modes of the substances, RAX will be capable to characterize the igneous phases, volatiles, organic species, and secondary alteration minerals at grain scale. RAX’s targets may be correlated, on the one hand to the orbital data to better approach the spatial distribution and stratigraphic relationship between the Phobos’ blue and red material units, and on the other hand to the mineral and rock types observed on the Mars’ surface by other Raman spectrometers to link their genesis (or not) (e.g. RLS [6], or Supercam [7]). The identified mineral assemblages can be used to determine whether Phobos is a captured asteroid rich in carbon and water, or is a remnant body of a giant impact to Mars. In addition, the information may also support the sample return selection and provide context information of the materials once they are in terrestrial laboratories. References. [1] T. Usui, et al., Space Sci. Rev. 216:49, 2020; [2] S. L. Murchie, D. T. Britt, C. M. Pieters., Space Science 102, 2014, 176–182; [3] C.M. Pieters, S. L. Murchie, N. Thomas, and D. Britt, Planetary and Space Science 102, 2014, 144-151; [4] P. Michel, et al., Earth, Planets and Space 74: 2, 2022; [5] Y. Cho et al., Earth, Planets and Space 73:232, 2021; [6] F. Rull et al., Astrobiology 17 (6-7), 2017, 627–654; [7] S. Maurice et al., Space Sci. Rev. 217, 2021.

Raman Laser Spectrometer (RLS) is the Pasteur Payload instrument of the ExoMars mission, within the ESA’s Aurora Exploration Programme, that will perform for the first time in an out planetary mission Raman spectroscopy. RLS is composed by SPU (Spectrometer Unit), iOH (Internal Optical Head), and ICEU (Instrument Control and Excitation Unit). iOH focuses the excitation laser on the samples (excitation path), and collects the Raman emission from the sample (collection path, composed on collimation system and filtering system). Its original design presented a high laser trace reaching to the detector, and although a certain level of laser trace was required for calibration purposes, the high level degrades the Signal to Noise Ratio confounding some Raman peaks. So, after the bread board campaign, some light design modifications were implemented in order to fix the desired amount of laser trace, and after the fabrication and the commitment of the commercial elements, the assembly and integration verification process was carried out. A brief description of the iOH design update for the engineering and qualification model (iOH EQM) as well as the assembly process are briefly described in this papers. In addition, the integration verification and the first functional tests, carried out with the RLS calibration target (CT), results are reported on.

A miniaturized diode-pumped solid-state laser (DPSSL) designed as part of the Raman laser spectrometer (RLS) instrument for the European Space Agency (ESA) Exomars mission 2020 is assembled and tested for the mission purpose and requirements. Two different processes were tried for the laser assembling: one based on adhesives, following traditional laser manufacturing processes; another based on a low-stress and organic-free soldering technique called solderjet bumping technology. The manufactured devices were tested for the processes validation by passing mechanical, thermal cycles, radiation, and optical functional tests. The comparison analysis showed a device improvement in terms of reliability of the optical performances from the soldered to the assembled by adhesive-based means.