Solar System Planetary Science

Research in Solar System planetary science spans the origin, evolution and present‐day processes affecting planets, moons, minor bodies and their interactions. The field addresses how protoplanetary disks assembled dust and gas into planetesimals and planetary embryos, how giant and terrestrial planets accreted and migrated, and how collisional and dynamical events sculpted the final architecture. Studies of chemical and isotopic compositions—both via remote sensing and laboratory analysis of meteorites and returned samples—reveal the thermal and volatile histories of planetary interiors, surfaces and atmospheres. Dynamical investigations, from n-body simulations to resonant dynamics and non‐gravitational forces, underpin our understanding of orbital stability, small-body populations and delivery of water and organics. Observations of comets, asteroids, planetary rings and exospheres illuminate present‐day activity, while space missions continue to expand the inventory of planetary bodies, refined ephemerides and detailed surface and subsurface characterisation. Together, these strands inform comparative planetology, constrain models of planet formation and migration, and guide future exploration and resource utilisation.

Research from Nature Portfolio

Spectroscopic mapping with the James Webb Space Telescope has for the first time directly detected water-vapour emission from a main-belt comet, confirming ice sublimation as the driver of its transient coma and establishing these bodies as a distinct population of volatile-bearing asteroids. Rapid-heating experiments on meteorite analogues of near-Sun asteroid Phaethon demonstrate that sulphur-bearing gases can be retained and released in repeated perihelion passages, accounting for its dust activity without fresh surface renewal and predicting a regolith dominated by olivine, iron sulphides, Ca-sulphates and hematite. High-precision analyses of Chang’e-5 mare basalts reveal exceptionally low water abundances (hundreds of μg g–1) and depleted mantle signatures, demonstrating that late-stage volcanism on the Moon was driven by heat rather than hydrous processes and extending the known duration of lunar magmatism to 2.03 Ga.

Research from all publishers

A dynamical study of active Centaurs and high-perihelion Jupiter-family comets has identified rapid “semimajor-axis jumps”—sharp decreases in orbital semimajor axis and eccentricity within centuries of observed outbursts—as a principal trigger for renewed activity, offering a predictive tool to identify objects poised for imminent activation. Dust-flux measurements by New Horizons beyond 55 au reveal higher than modelled interplanetary dust densities, indicating that Kuiper Belt object collisions and photosputtering produce a more extended dust distribution than previously predicted. Analyses of returned Ryugu samples show millimetre-scale chromium isotopic heterogeneities driven by aqueous alteration and brecciation, demonstrating that parent-body water circulation can generate isotopic anomalies and that presolar nanoparticle fractionation contributes to the preserved isotopic record.

Solar System Planetary Science publication trend

The graph below shows the total number of articles in solar system planetary science across all publications each year (not limited to Nature Index journals).

Technical terms

Protoplanetary disk: A rotating circumstellar disk of gas and dust from which planetesimals and planets form.

Accretion: The process by which particles and bodies coalesce under gravity or drag forces to grow larger aggregates.

Planetesimal: A kilometre‐scale solid object formed by coagulation of dust grains, representing a stepping stone to planetary embryos.

Semimajor‐axis jump (“a‐jump”): A rapid decrease in orbital semimajor axis and eccentricity that can alter perihelion heating and trigger volatile activity in small bodies.

Main‐belt comet: An asteroid-belt object that repeatedly exhibits comet‐like activity driven by sublimation of near-surface ices.

Isotopic anomaly: A deviation in the relative abundance of isotopes from a standard, indicating distinct formation or alteration processes.

References

1. Spectroscopic identification of water emission from a main-belt comet. Nature (2023).
2. Rapid heating rates define the volatile emission and regolith composition of (3200) Phaethon. Nature Communications (2024).
3. A dry lunar mantle reservoir for young mare basalts of Chang’e-5. Nature (2021).
4. Two-billion-year-old volcanism on the Moon from Chang’e-5 basalts. Nature (2021).
5. Semimajor-axis Jumps as the Activity Trigger in Centaurs and High-perihelion Jupiter-family Comets. The Astrophysical Journal Letters (2024).
6. New Horizons Venetia Burney Student Dust Counter Observes Higher than Expected Fluxes Approaching 60 au. The Astrophysical Journal Letters (2024).
7. Water circulation in Ryugu asteroid affected the distribution of nucleosynthetic isotope anomalies in returned sample. Science Advances (2023).