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Abstract Japan Aerospace Exploration Agency (JAXA) plans a Phobos sample return mission (MMX: Martian Moons eXploration). In this study, we review the related works on the past climate of Mars, its evolution, and the present climate and weather to describe the scientific goals and strategies of the MMX mission regarding the evolution of the Martian surface environment. The MMX spacecraft will retrieve and return a sample of Phobos regolith back to Earth in 2029. Mars ejecta are expected to be accumulated on the surface of Phobos without being much shocked. Samples from Phobos probably contain all types of Martian rock from sedimentary to igneous covering all geological eras if ejecta from Mars could be accumulated on the Phobos surface. Therefore, the history of the surface environment of Mars can be restored by analyzing the returned samples. Remote sensing of the Martian atmosphere and monitoring ions escaping to space while the spacecraft is orbiting Mars in the equatorial orbit are also planned. The camera with multi-wavelength filters and the infrared spectrometer onboard the spacecraft can monitor rapid transport processes of water vapor, dust, ice clouds, and other species, which could not be traced by the previous satellites on the sun-synchronous polar orbit. Such time-resolved pictures of the atmospheric phenomena should be an important clue to understand both the processes of water exchange between the surface/underground reservoirs and the atmosphere and the drivers of efficient material transport to the upper atmosphere. The mass spectrometer with unprecedented mass resolution can observe ions escaping to space and monitor the atmospheric escape which has made the past Mars to evolve towards the cold and dry surface environment we know today. Together with the above two instruments, it can potentially reveal what kinds of atmospheric events can transport tracers (e.g., H2O) upward and enhance the atmospheric escape. Graphical Abstract

Japan Aerospace Exploration Agency (JAXA) plans a Phobos sample return mission (MMX: Martian Moons eXploration). In this study, we review the related works on the past climate of Mars, its evolution, and the present climate and weather to describe the scientific goals and strategies of the MMX mission regarding the evolution of the Martian surface environment. The MMX spacecraft will retrieve and return a sample of Phobos regolith back to Earth in 2029. Mars ejecta are expected to be accumulated on the surface of Phobos without being much shocked. Samples from Phobos probably contain all types of Martian rock from sedimentary to igneous covering all geological eras if ejecta from Mars could be accumulated on the Phobos surface. Therefore, the history of the surface environment of Mars can be restored by analyzing the returned samples. Remote sensing of the Martian atmosphere and monitoring ions escaping to space while the spacecraft is orbiting Mars in the equatorial orbit are also planned. The camera with multi-wavelength filters and the infrared spectrometer onboard the spacecraft can monitor rapid transport processes of water vapor, dust, ice clouds, and other species, which could not be traced by the previous satellites on the sun-synchronous polar orbit. Such time-resolved pictures of the atmospheric phenomena should be an important clue to understand both the processes of water exchange between the surface/underground reservoirs and the atmosphere and the drivers of efficient material transport to the upper atmosphere. The mass spectrometer with unprecedented mass resolution can observe ions escaping to space and monitor the atmospheric escape which has made the past Mars to evolve towards the cold and dry surface environment we know today. Together with the above two instruments, it can potentially reveal what kinds of atmospheric events can transport tracers (e.g., H2O) upward and enhance the atmospheric escape. [ABSTRACT FROM AUTHOR]

The formation of dusty plasma due to photoelectric and electrostatic processes in the near-surface layer of the illuminated part of Deimos, the satellite of Mars, is discussed. The parameters characterizing the trajectories of motion of dust grains are determined on the basis of a physico-mathematical model for a self-consistent description of densities of photoelectrons and dust grains above the illuminated part of Deimos. It is shown that the damping of oscillations of a dust grain above the Martian satellite's surface is associated with variations in its charge that is consistent with the concept of anomalous dissipation that follows from processes associated with variations in the charges of dust grains. It is demonstrated that for the majority of dust grains that are lifted above Deimos's surface due to photoelectric and electrostatic processes, the damping time of their oscillations turns out to be longer than the daylight time, i.e., the non-stationarity of the dusty plasma system above the illuminated surface of Deimos manifests almost during the entire duration of the day on it. The maximum altitudes to which dust grains lift and maximum charge numbers that can be achieved by dust grains of different sizes are determined, and the typical densities of dust grains and photoelectrons above Deimos are estimated. More detailed information on the properties of its soil, which is expected to be obtained in future space missions, is required to obtain more definite data about the parameters of the plasma–dust system in the vicinity of Deimos. [ABSTRACT FROM AUTHOR]

Abstract: Background: Acute liver failure (ALF) as a result of mushroom poisoning is associated with a high mortality (particularly in children), despite optimal medical therapy (OMT), including charcoal haemoperfusion and haemodiafiltration. MARS is a new, cell-free, extracorporeal liver assistance method utilizing an albumin dialysate for the removal of albumin-bound toxins. Methods: We describe the first series in the literature (also first MARS treatments in Romania) with ALF because of mushroom poisoning in children (M/F = 2/4, age = 7–16 years). Liver function was evaluated pre-MARS and 15-min post-MARS, 24 h following each treatment and 30 days post-MARS. Findings: All patients had severe hepatic dysfunction: hepatic encephalopathy (HE; four grade II, one grade III, one grade IV), ALT = 4082 (3400–5600) IU/L, bilirubin = 6.3 (2–10) mg/dL, prothrombin time (PT) = 52.5 (23–141) s. MARS was uneventful and well-tolerated. Two 6-h sessions per patient were performed with a similar immediate impact on liver tests: mean drop in ALT of -33 and -35%, respectively, and in bilirubin of -39 and -36%, respectively. ALT levels 24 h following MARS-1, remained unchanged but continued to drop by a further -28% following MARS-2. By contrast, all patients had a significant rebound in bilirubin (+39%) 24 h following MARS-1; however, following MARS-2 a rebound was seen only in two cases (+220%). PT improved by 37% after MARS-1 and normalized in four patients after MARS-2. Outcome: Four patients survived and completely recovered the hepatic function. Negative prognostic markers: lack of complete correction of PT, continuous rebound and increase in bilirubin, and lack of improvement in HE post-MARS-1. Survival in six well-matched cases, treated by OMT = 0/6 (P < 0.05). Conclusions: MARS is a safe and highly effective depurative therapy in children with ALF. Survival is predicted only by the impact/results of the initial MARS sessions and not by any of the baseline parameters. [ABSTRACT FROM AUTHOR]