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Double Asteroid Redirection Test (DART) mission impacted Dimorphos to test asteroid deflection. Here, the authors show that post-impact spectra largely match pre-impact properties, with only subtle variations probably linked to mutual events and to the evolution of the ejecta dust.

Studying craters on atmosphere-less bodies can unlock information about planetesimal histories. Here, Marchi et al. present results from the NASA Dawn mission to Ceres showing that craters >100–150 km in size are largely absent, and find that Ceres’ internal evolution is responsible for their absence.

From spectra and images of Vesta, it is suggested that the dark patches on Vesta are formed of infalling hydrated carbonaceous material and the bright patches are uncontaminated Vesta soil.

Whereas space weathering of some airless bodies, such as the Moon, occurs through the accumulation on regolith of nanophase metallic particles, spectroscopic data show that space weathering of the asteroid Vesta occurs through the small-scale mixing of diverse surface components, which gradually generates locally homogenized upper regolith.

Observations of water ice on the surface of comet 67P/Churyumov–Gerasimenko show the ice appearing and disappearing in a cyclic pattern that follows local illumination conditions, providing a source of localized activity and leading to cycling modification of the ice abundance on the surface.

Although olivine was expected to occur within the deep, south-pole basins of asteroid Vesta, which are thought to be excavated mantle rocks, spectral data from NASA’s Dawn spacecraft show that it instead occurs as near-surface materials in Vesta’s northern hemisphere.

Infrared spectra of (1) Ceres acquired at distances of 82,000 to 4,300 kilometres from the surface indicate widespread ammoniated phyllosilicates; the presence of ammonia suggests that material from the outer Solar System was incorporated into Ceres.

Spectroscopic data obtained at high spatial resolution from Dawn detected the presence of fresh chloride salts at Cerealia Facula on Ceres. The spatial distribution of the hydration level of these salts suggests that they surfaced a maximum of a few centuries ago and that the upwelling of salty fluids may still be active.

Using infrared wavelengths, micrometre-sized water-ice grains have been identified on the nucleus (which is mostly coated in a dark material) of comet 67P/Churyumov–Gerasimenko.

Infrared and neutron spectroscopic observations by Dawn give contrasting results on the elemental composition of Ceres’s surface, which can be reconciled by assuming that Ceres’s surface contains ~20 wt% of carbon, coming from impacts by carbonaceous asteroids and/or generated by extensive aqueous alteration.

High-resolution near-infrared observations of the Occator bright areas on the dwarf planet Ceres suggest that the bright material is mostly made up of endogenous sodium carbonate.

Venus has a bright 'dipole' double-eye feature at the centre of a vast vortex that rotates around the north pole, and is surrounded by a cold 'collar'. Observations of Venus' south polar region are reported, where clouds with morphology much like those around the north pole are seen, but rotating somewhat faster.

Observations of infrared emission from CO₂, O₂ and NO established that photochemical and dynamic activity controls the structure of the upper atmosphere of Venus, but were unable to identify the altitude of the emission. But it is reported here that day-side CO₂ emission extends from 90–120 km altitude, with a peak at ∼115 km. Night-side O₂ emission peaks at 96 km and is visible over the range 95–100 km.

Yellowish bright areas around the Dantu crater on Ceres, identified using the Dawn Visible and Infrared Mapping Spectrometer, represent recent emplacement or excavation of large quantities of ammonium-rich materials and suggest the presence of subsurface fluids.