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Context. A stellar occultation by Neptune’s main satellite, Triton, was observed on 5 October 2017 from Europe, North Africa, and the USA. We derived 90 light curves from this event, 42 of which yielded a central flash detection. Aims. We aimed at constraining Triton’s atmospheric structure and the seasonal variations of its atmospheric pressure since the Voyager 2 epoch (1989). We also derived the shape of the lower atmosphere from central flash analysis. Methods. We used Abel inversions and direct ray-tracing code to provide the density, pressure, and temperature profiles in the altitude range ~8 km to ~190 km, corresponding to pressure levels from 9 µbar down to a few nanobars. Results. (i) A pressure of 1.18 ± 0.03 µbar is found at a reference radius of 1400 km (47 km altitude). (ii) A new analysis of the Voyager 2 radio science occultation shows that this is consistent with an extrapolation of pressure down to the surface pressure obtained in 1989. (iii) A survey of occultations obtained between 1989 and 2017 suggests that an enhancement in surface pressure as reported during the 1990s might be real, but debatable, due to very few high S/N light curves and data accessible for reanalysis. The volatile transport model analysed supports a moderate increase in surface pressure, with a maximum value around 2005-2015 no higher than 23 µbar. The pressures observed in 1995-1997 and 2017 appear mutually inconsistent with the volatile transport model presented here. (iv) The central flash structure does not show evidence of an atmospheric distortion. We find an upper limit of 0.0011 for the apparent oblateness of the atmosphere near the 8 km altitude., Astronomy & Astrophysics, 659, ISSN:0004-6361, ISSN:1432-0746

Alla mia meravigliosa famiglia, This document contains the results and the discussion on the interchannel test performed during the Instrument Check Out Phase (ICO#3) of the Spectrometers and Imagers for MPO BepiColombo Integrated Observatory SYStem (SIMBIO-SYS).

Alla mia splendida famiglia, In this document we describe all the tests to be performed during the Instrument CheckOut (ICO) # 03 for the Spectrometers and Imagers for MPO BepiColombo Integrated Observatory SYStem (SIMBIO-SYS).

In this document we will describe all the tests performed during the fourth Instrument Checkout (ICO#04) for the Spectrometers and Imagers for MPO BepiColombo Integrated Observatory SYStem (SIMBIO-SYS). The checkout session was performed between December 13th and 14th 2020. For each test it will be presented the pipeline report and, where necessary, a discussion on the detected anomalies.

The present document has been issued to describe the Instrument Check Out Phase (ICO#3) Tests of HRIC, channel of the Spectrometers and Imagers for MPO BepiColombo Integrated Observatory SYStem (SIMBIO-SYS).

Un ringraziamento va ad ASI per il supporto per il progetto., In this document, we reported the history of the tests performed on the STC detector in the first two years of the BepiColombo’s cruise phase. The scope of these tests was to monitor the dark current behavior of the STC channel’s detector. A detailed description is provided for each test phase: data acquired, the deducted results and conclusions. The STC Channel is part of SIMBIO-SYS, a scientific payload of the BepiColombo ESA-JAXA mission to Mercury. During the NECP (Near-Earth Commissioning Phase ), all the initial commissioning activities were completed and the three channels of SIMBIO-SYS have operated properly demonstrating that all the channels and subsystems worked nominally. Since then, every six months different instrument checkouts have been carried-out to check the performance of the three SIMBIO-SYS channels and improve their calibration. This document reports the conclusion on the Dark calibration of STC Channel due to the analysis of the ICOs tests.

In this document, we will describe a software developed to convert a STACK, a list of TeleCommand and related parameters for the Spectrometer and Imagers for MPO BepiColombo Integrated Observatory SYStem (SIMBIO‐SYS) instrument suite onboard the ESA mission BepiColombo to Mercury, in a sequence of commands that can be ingested by the instrument Electrical Model (EM) located in Orsay. The STACK is provided by the Mission Operation Center (MOC) at ESA‐ESOC in XLSX format before each in‐flight instrument test for final approval by the SIMBIO‐SYS Team. This document reports the software features, functionalities, and syntax. The software is a MATLAB script. It could be used as a standalone or integrated into a pipeline.

Alla mia splendida famiglia e a Silvio Biazzo., This document will briefly report the results of the tests performed during the Instrument Checkout (ICO) # 02 for the Spectrometers and Imagers for MPO BepiColombo Integrated Observatory SYStem (SIMBIO-SYS).

In this document we will describe all the tests performed during the third Instrument Checkout (ICO#03) for the spectrometers and Imagers for MPO BepiColombo Integrated Observatory SYStem (SIMBIO-SYS). The checkout session was performed between June 24th and 25th 2020. For each test it will be presented the pipeline report and, where necessary, a discussion on the detected anomalies.

A Silvio, amico e conforto., This document, in according to the Spectrometers and Imagers for MPO BepiColombo Integrated Observatory SYStem (SIMBIO-SYS) Technical Note, Layout and Data flow agreement, reports all the SIMBIO-SYS Flight Operation Procedures (FOPs) to be used during the operational phases of the instrument. This issue represents a new review of the SIMBIO-SYS FOP official database considering all the improvements made after the first two Instrument Check Outs (ICO) and before the third.

Si ringrazia ASI per i finanziamenti che hanno reso possibile l'avanzamento di questo progetto., The present document has been issued to describe the ICO#3 (Third Instrument Check Out Phase) Tests of STC, channel of the Spectrometers and Imagers for MPO BepiColombo Integrated Observatory SYStem (SIMBIO-SYS).

Si ringrazia ASI per aver reso possibile il progetto, This document, in accordance with the Spectrometers and Imagers for MPO BepiColombo Integrated Observatory SYStem (SIMBIO-SYS) Technical Note, Layout and Data flow agreement detailed in [RD.1], reports all the interdependence rules between the parameters (i.e., PSSxxx) in a single SIMBIO-SYS TeleCommand (TC) to make it compatible with respect to the Main Electronics (ME) Application SoftWare ASWv2.7) and so being executable. These rules are fundamental in building correct Flight Operation procedures (FOPs) and all other higher-level commanding sequences as Payload Direct Operation Request (PDOR), Payload Operation Request (POR), Memory Operation Request (MOR) and Instrument TimeLine (ITL) that use FOPs with open (i.e., formal) parameters. This is a sort of “living document” since present version describes two rules which are considered, for the time being, the most important ones: 1. Compatibility between commanded windows size and Compression settings of the Compression Unit (CU) in the ME 2. Definition of the lower limit of the Repetition Time (RT) 3. On-board processing for data refinement

Alla mia meravigliosa famiglia, In this document we describe all the tests to be performed during the Instrument CheckOut (ICO) # 04 for the Spectrometers and Imagers for MPO BepiColombo Integrated Observatory SYStem (SIMBIO-SYS).

The Martian Moon eXploration mission (MMX), currently developed by the Japan Aerospace Exploration (JAXA) will aim at studying Mars satellites and return samples from Phobos to decipher the history of the Martian system. MMX mission is to be launched in September 2024 and arrive in Mars system on August 2025, will stay three years in Quasi Satellite Orbits (QSO) around Phobos, and will land for several hours on Phobos to collect at least 10g of Phobos regolith before returning to Earth. Among the mission instrument suite is the near-Infrared Spectrometer MIRS (MMX InfraRed Spectrometer) provided by CNES and built at LESIA-Paris Observatory in collaboration with four other French laboratories (LAB, LATMOS, LAM, IRAP-OMP) and in close collaboration with JAXA and MELCO. MIRS is an imaging spectrometer from 0.9 to 3.6 µm, with a spectral resolution better than 20 nm. The IFOV is 0.35 mrad and FOV of +/-1.65°. The SNR is higher than 100 up to 3.2 µm in a maximum integration time less than 2s. For Mars observation MIRS is expected to perform observations at 10 km spatial resolution, with a spectral radiometric absolute and relative accuracies of 10% and 1% respectively. Given MIRS spectral range, expected Signal-to-Noise ratio, and observation windows, a certain numbers of high priority targets have been set to achieve MMX goal of Constrain transport processes for dust and water near the Martian Surface, continuous observations of the mid-to low-latitude distributions of dust storms, ice clouds and water vapor in the Martian atmosphere (Barucci et al. 2021, Ogohara et al. 2021), summarized in Table 1. Simulated spectra of Martian atmosphere as observed by MIRS are provided in Figure 1. Table 1: List of MIRS main science targets for Mars observations (adapted from Barucci et al. 2021). Target Parameters Spectral range Ice cloud formation and evolution Water ice 1.5, 2 and 3 µm Dust clouds / storms formation and evolution Dust CO2 band @2.7 µm 0.9-3.6 µm continuum Water cycle H2O vapor 2.6 µm Atmospheric dynamics and composition Surface pressure CO2 band @ 2.0 µm CO 2.3 µm Limb observations for middle atmosphere O2 day-glow 1.27 µm Figure 1: Simulated MIRS spectra for typical Mars observation (from Barucci et al. 2021). Plain curves correspond to clear sky conditions, and the dashed ones include the effects of dust or water ice clouds. For gases, CO2, CO, and water vapor are calculated separately and reported in red, orange, and blue curves, respectively. MMX QSO around Phobos will result in a quasi-circular orbit around Mars with a period of ~7h, providing more than 3 hours window to Mars observation when Phobos observation is not possible. Several observation strategies, still in discussion, will be possible to maximize either temporal or spatial coverage of Mars and its atmosphere by MIRS. These strategies span from observations with a 30 minutes temporal resolution of a limited zone, to a complete coverage for low and mid latitude in a few orbits (Ogohara et al. 2021, Barucci et al. 2021). Limb observations may also be performed to obtain high vertical resolution observations of the Martian atmosphere. MIRS observations will provide further constraints on dust and water transport processes in the Martian atmosphere, by monitoring the distributions of dust content and storms, water ice clouds and water vapor. CO2 (and thus pressure) will be monitored through the CO2 2.0 µm band. Water vapor will be monitored on a daily basis using its 2.6 µm band (Maltagliati et al. 2008) and water ice clouds through their spectral features between 0.9 and 3.6 µm (Olsen et al. 2019). MIRS should also be able to detect CO 2.35 µm and O2 at 1.27 µm. MIRS spectra will also allow for estimations of the water adsorbed in the surface regolith. Finally, MIRS will be operated in close collaboration with the OROCHI (Optical Radiometer composed of Chromatic Imagers) and TENGOO (Telescopic Narrow Angle Camera) instruments. This will enable efficient monitoring and reactivity to investigate short lifespan events in Martian atmosphere. This will also render possible the investigation of CO2 clouds following the procedure proposed by Vincendon et al. 2011 for Mars Express observations. The reflectance spectrum from the light backscattered by atmospheric aerosols can be obtained by comparing successive observations of identical zones on Mars within a short time and with varying phase angles. Such a set of measurements permits to decorrelate the surface reflectance signal from the light scattered by the aerosols suspended in the atmosphere and gives information on the aerosols size and their composition properties averaged over the line of sight. Previous measurements showed a particle size distribution having an effective radius of 1.2±0.2 μm (Erard et al. 1994). The retrieved parameters include the scattering albedo, the phase function of the aerosols, the optical thickness, τ, of the atmosphere at the time of observation and the aerosols size distribution. In summary, MIRS observations, together with the ones from MSA, OROCHI and TENGOO, will help better understand the interdependencies of species and their roles in the Martian water, CO2 and dust cycles, thanks to long term monitoring of these key constituents of Mars atmosphere. References Barucci et al. 2021, MIRS an Imaging Spectrometer for the MMX mission, accepted for publication in Earth Planets and Space Erard, S., Mustard, J., Murchie, S., Bibring, J. P., Cerroni, P., & Coradini, A. (1994). Martian aerosols: Near-infrared spectral properties and effects on the observation of the surface. Icarus, 111(2), 317-337. Ogohara et al. 2021, The Mars system revealed by the Martian Moons eXploration mission, accepted for publication in Earth Planets and Space Vincendon et al. 2011, New near-IR observations of mesospheric CO2 and H2O clouds on Mars, JGR Planets 116, 0-02.

Alla mia meravigliosa famiglia., This document will briefly report the results of the tests performed during the Instrument Checkout (ICO) # 01 for the Spectrometers and Imagers for MPO BepiColombo Integrated Observatory SYStem (SIMBIO-SYS)

This document describes the use of the software developed to solve the issues founded on the EDDS system to retrieve the SIMBIO-SYS raw data used as input for the data reduction pipeline [RD2]. In the cited TC was discussed that a packet could be received by two, or more, different ground stations. At ESOC levels the packets result differently. They have different SCOS headers but the same data. Those packets introduce a duplication of one or more subframes compromising the scientific data.

The document describes the software used to extract the Events from the telemetry of the Spectrometers and Imagers for MPO BepiColombo Integrated Observatory SYStem (SIMBIOSYS). The document provides documentation on the output file, also.

In this document we briefly report the tests performed during the delta- Near Earth Commissioning Phase (NECP) for the Spectrometers and Imagers for MPO BepiColombo Integrated Observatory SYStem (SIMBIO- SYS) and discuss the obtained results.

Alla mia meravigliosa famiglia, In this document we describe all the tests to be performed during the delta-Near Earth Commissioning Phase (dNECP) for the Spectrometers and Imagers for MPO BepiColombo Integrated Observatory SYStem (SIMBIO-SYS).

Alla mia meravigliosa famiglia, This document contains the results and the discussion on the interchannel tests performed during the delta-Near Earth Commissioning Phase (dNECP) for the Spectrometers and Imagers for MPO BepiColombo Integrated Observatory SYStem (SIMBIO-SYS). The dNECP was requested by the SIMBIO-SYS team to verify the behaviour of the instrument during the execution of the NECP tests. In particular, SIMBIO-SYS repeated the Interchannel test limiting to the “Orbit Test” whose results in NECP did not confirm the correct operation of the instrument.

Alla mia splendida famiglia, In this document we describe all the tests to be performed during the Instrument CheckOut (ICO) # 02 for the Spectrometers and Imagers for MPO BepiColombo Integrated Observatory SYStem (SIMBIO-SYS).