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The Margin Unit of Jezero crater contains olivine with a forsterite content similar to the olivine cumulates in the crater floor, according to an approach which uses X-ray data from the Perseverance rover to analyse monocrystalline olivine composition

Here the authors report a randomized controlled trial showing that a previously developed artificial intelligence model estimates patient mortality risk as accurately as doctors and standard risk scores, but did not change clinical care decisions in the emergency department. This suggests that prediction accuracy alone does not necessarily translate into real-world clinical impact.

A modelling study suggests that Mars had a desert-like climate with intermittent liquid-water oases regulated by a negative feedback among solar luminosity, liquid water and carbonate formation.

ESA’s Trace Gas Orbiter reveals that the winter night sky on Mars emits visible light between 50 km and 70 km altitude in the polar regions. This nightglow should be observable with simple space camera systems and the naked eyes of future Mars astronauts.

It is thought that water flowed on the surface of Mars in the geological past during periods of high orbital obliquity. Here, the authors assess how much liquid water was present and suggest that debris flows occurred at Earth-like frequencies during high-obliquity periods in the past million years.

The surface of Mars exhibits intriguing outcrops of layered Fe sulfate minerals that transformed through heating. This study combines lab analyses and remote sensing at Mars to advance the understanding of active chemistry and geothermal processes.

Ancient valleys suggest a warm early Mars where liquid water flowed, but a greenhouse effect strong enough to offset a dim early Sun has been difficult to explain. Climate simulations suggest that sufficient concentrations of the greenhouse gases CO₂ and H₂ — outgassed during volcanic eruptions — could have warmed Mars above water’s freezing point.

A geological, petrographic and geochemical survey of distinctive mudstone and conglomerate outcrops of the Bright Angel formation on Mars reveals textures, chemical and mineral characteristics, and organic signatures that warrant consideration as potential biosignatures.

The Perseverance rover has made the most definitive identification of Fe-phosphate minerals on Mars to date. High-resolution chemical and textural PIXL analyses suggest they originally formed after vivianite in a potentially habitable environment.

The MAVEN spacecraft observed brightening in the Lyman-α line correlated with solar wind activity, which can be attributed to auroral activity by solar wind protons interacting with the Martian neutral hydrogen corona. Proton aurorae are normally seen at Earth only.

Patterns of erosion and deposition by some slope streaks on Mars are consistent with a dry dust avalanche origin, according to an analysis of orbital images before and after new streaks formed.

Most of Mars’s initial water has been lost through atmospheric escape, but seasonal imbalances of measured hydrogen loss compared to oxygen are enigmatic. Photochemical models suggest that seasonal water vapour at high altitudes enhances hydrogen loss rates.

Dark streaks that appear on the surface of Mars during warm seasons have been observed at the mid-latitudes and tentatively attributed to the flow of briny water. Imagery from the Mars Reconnaissance Orbiter over multiple Mars years suggests that these seasonally active features are also present in equatorial regions, where liquid surface water is not expected.

Emplacement of the north polar cap of Mars is investigated by combining viscoelastic deformation calculations and observations, showing that it formed over the last 1.7–12.0 Myr atop a stiff lithosphere and high-viscosity mantle (10²² Pa s), and that glacial isostatic adjustment could be further constrained.

The Martian dichotomy boundary receded hundreds of kilometres in the Mawrth Vallis region and left behind mounds that record changing aqueous conditions during the Noachian (4.1–3.7 Ga), according to a geomorphological and spectroscopic study.

Results from the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) of phyllosilicate-rich regions are reported. It is discovered that stratigraphic relationships show olivine-rich materials overlying phyllosilicate-bearing units, indicating cessation of aqueous alteration before emplacement of the olivine-bearing unit. It is also found phyllosilicates in sedimentary deposits clearly laid by water, pointing to a rich diversity of Noachian environments conducive to habitability.

Mars’ distinctive red colour attributed to ferrihydrite, a type of rust mineral. This finding suggests Mars experienced a cold and wet environment before transitioning to its current desert state.

Quartz-rich clasts in Martian meteorite NWA 7533 indicate the presence of granitic rocks on early Mars that formed via hydrothermal activity and impact melting, according to petrologic and in situ geochemical analyses.

Annular (zonally symmetric) atmospheric modes, common on Earth, are found on both Mars and Titan via observations and general circulation models. On Mars, they have considerable impact on dust activity and could be used to predict dust storms. On Titan, they could be linked to sporadic cloud outbursts.

High-resolution spacecraft imagery has revealed transient deposits that appear in the early mornings of cold seasons at the high altitudes of the Tharsis volcanoes on Mars, consistent with water frost of atmospheric origin.

Aluminum-rich float rocks at Jezero crater display geochemical characteristics that are more similar to terrestrial weathered palaeosols than to hydrothermal deposits, according to a comparison of Perseverance rover elemental data with terrestrial analogues

When the cone angle between the solar wind velocity and the solar wind magnetic field is small at Mars, the induced magnetosphere degenerates.

Wind power can be an oft-neglected source of energy for future human exploration missions on Mars, especially coupled with solar power. Modelling shows that solar and wind energy can fully power such missions for more than half of the Martian year for ten regions of interest identified by NASA. Another 13 promising sites are identified.

Analysis of interactions between the wheels of the Zhurong rover and the terrain along the rover’s traverse reveals soils with high bearing strength and cohesion.

Analysis of radio science data from the NASA InSight Mars lander reveals details of the rotation of the planet, which have been used to determine fundamental information about its core, mantle and atmosphere.

Using data gathered from the microphones of the Perseverance rover, the first characterization of the acoustic environment on Mars is presented, showing two distinct values for the speed of sound in CO₂-dominated atmosphere.

Although the Martian landscape presents evidence of wind erosion, sand-moving winds on Mars were thought to be rare due to the thin atmosphere. Here, the authors show that sand transport occurs daily and that the resulting sand flux varies seasonally.

We invert Rayleigh wave ellipticity curves extracted from ambient seismic vibrations at the InSight landing site to resolve, for the first time on Mars, the shallow subsurface to around 200 m depth. While our seismic velocity model is largely consistent with the expected stacks of lava flows, we find a seismic low velocity zone at about 30 to 75 m depth that we interpret as a sedimentary layer sandwiched between layers of basalt flows.

The InSight spacecraft landed on Mars on November 2018. Here, the authors characterize the surficial geology of the landing site and compare with observations and models derived from remote sensing data prior to landing and from ongoing in situ geophysical investigations of the subsurface.

Unique microorganisms of a fossil river delta in the Atacama Desert unveil the current limits of life detection on Mars.

Mars likely evolved from a warmer, wetter early state to the cold, arid current climate, but this evolution is not reflected in recent observations and measurements. Here, the authors derive quantitative constraints on the atmospheric pressure through time, identifying a mechanism that explains the carbon data.

Dust storms on Mars drive water escape to space. Here, the authors show the impact Martian dust storms have on the abundance of atmospheric hydrogen and oxygen, and how this helps to overall oxidize the Martian atmosphere.

Observations by the Curiosity rover at Gale Crater on Mars indicate that high-frequency wet–dry cycling occurred on the early Martian surface, indicating a possible seasonal climate conducive to prebiotic evolution on early Mars.

Rare earth elements are used in electronics, but increase in demand could lead to low supply. Here the authors conduct experiments on the International Space Station and show microbes can extract rare elements from rocks at low gravity, a finding that could extend mining potential to other planets.

The crust beneath the InSight lander on Mars is altered or fractured to 8–11 km depth and may bear volatiles, according to an analysis of seismic noise and wave scattering recorded by InSight’s seismometer.

Using high-resolution orbital imagery of the Martian surface, the authors Salese et al. here describe the first discovered stratigraphic product of multiple extensive fluvial-channel belts in an exposed vertical section at Izola Mensa in the northwestern rim of the Hellas Basin.

Lake breach flooding rapidly eroded almost a quarter of the volume of incised valleys on early Mars, influencing the topography of the wider Martian landscape.

The seasonal cycle in the methane mixing ratio observed at Gale Crater on Mars can be explained by adsorption onto and diffusion through the regolith, suggests a one-dimensional numerical model with geological constraints.