Related papers: The Climate of Early Mars
Mars is the Solar System's canonical small, rocky planet that transitioned from early geologic activity and surface liquid water to a cold and arid planet with a thin, cold, CO$_2$-dominated atmosphere. The evolution of Mars, in the context…
The presence of the ancient valley networks on Mars indicates that the climate at 3.8 Ga was warm enough to allow substantial liquid water to flow on the martian surface for extended periods of time. However, the mechanism for producing…
Latest research in planet formation indicate that Mars formed within a few million years (Myr) and remained a planetary embryo that never grew to a more massive planet. It can also be expected from dynamical models, that most of Mars'…
The dynamics of Mars' obliquity are believed to be chaotic, and the historical ~3.5 Gyr (late-Hesperian onward) obliquity probability density function (PDF) is high uncertain and cannot be inferred from direct simulation alone. Obliquity is…
The decay of the martian atmosphere - which is dominated by carbon dioxide - is a component of the long-term environmental change on Mars from a climate that once allowed rivers to flow to the cold and dry conditions of today. The minimum…
Martian surface morphology implies that Mars was once warm enough to maintain persistent liquid water on its surface. While the high D/H ratios (~6 times the Earth's ocean water) of the current martian atmosphere suggest that significant…
Sedimentary deposits characterized by the Mars Science Laboratory Curiosity rover provide evidence that Gale crater, Mars intermittently hosted a fluvio-lacustrine environment during the Hesperian. However, estimates of the CO2 content of…
Lakes existed on Mars later than 3.6 billion years ago, according to sedimentary evidence for deltaic deposition. The observed fluvio-lacustrine deposits suggest that individual lake-forming climates persisted for at least several thousand…
Oxygen isotopes in marine cherts have been used to infer hot oceans during the Archean with temperatures between 60{\deg}C (333 K) and 80{\deg}C (353 K). Such climates are challenging for the early Earth warmed by the faint young Sun. The…
The ion escape of Mars' CO$_2$ atmosphere caused by its dissociation products C and O atoms is {simulated} from present time to $\sim 4.1$ billion years ago (Ga) by {numerical models of the upper atmosphere and its interaction with the…
Despite decades of scientific research on the subject, the climate of the first 1.5 Gyr of Mars history has not been fully understood yet. Especially challenging is the need to reconcile the presence of liquid water for extended periods of…
Mars exploration motivates the search for extraterrestrial life, the development of space technologies, and the design of human missions and habitations. Here we seek new insights and pose unresolved questions relating to the natural…
Mars today has no active volcanism and its atmosphere is oxidizing, dominated by the photochemistry of CO2 and H2O. Using a one-dimensional photochemical model, we consider whether plausible volcanic gas fluxes could have switched the…
The long-standing debate on the existence of ancient oceans on Mars has been recently revived by evidence for tsunami resurfacing events that date from the Late Hesperian geological era. It has been argued that these tsunami events…
The formation of gullies on Mars has often been attributed to the melting of (sub)surface water ice. However, melting-based hypotheses generally overlook key processes: (1) sublimation cooling by latent heat absorption, (2) the…
Recent papers by Ansari et al. (2024, Science Advances 10, eadn4650) and Richardson et al. (2025, arXiv eprint 2504.01455) have suggested that global warming of the Martian surface ('terraforming') by 35 K to sustain local habitats above…
Mars provides a critical analog to once habitable exoplanets that have since lost their surface liquid water. The current atmospheric state of Mars retains the chemical fingerprints of that transition, including isotopic signatures of…
This roadmap outlines research pathways to determine whether Mars could be warmed with non-biological methods. It does not presuppose that warming Mars is desirable; its purpose is to identify what would need to be true for Mars to be…
It is still unknown how much water has escaped from Mars during its history. Hydrogen escape from Mars's atmosphere probably played a major role in drying the planet, but present-day Hloss rates (about 3x10^26 atoms per second on average)…
The planetary differentiation models of Mars are proposed that take into account core-mantle and core-mantle-crust differentiation. The numerical simulations are presented for the early thermal evolution of Mars spanning up to the initial…