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Lunar impact basins formed during the magma ocean solidification should have formed almost unidentifiable topographic and crustal thickness signatures, thus may escape detection. This result allows for a higher impact flux in the earliest epoch of Earth-Moon evolution.

The recent discovery of diamond graphite inclusions in the Earth's oldest zircon grains from the Jack Hills metasediments in Western Australia provides a unique opportunity to investigate Earth's earliest known carbon reservoir. This paper reports ion microprobe analyses of the carbon isotope composition of these diamond-graphite inclusions and finds low carbon isotopic ratios, which may reflect deep subduction of biogenic surface carbon. But such carbon isotope values may also be produced by inorganic chemical reactions.

How the atmosphere, hydrosphere and surface materials interacted on early Mars is poorly understood. Oxygen isotopic composition of zircon grains in a martian meteorite reveals a prolonged history of exchange between martian regolith and atmosphere.

The primitive Moon was covered with a thick layer of melt known as the lunar magma ocean, whose crystallization resulted in the Moon’s surface as it is observed today. Dating of the oldest zircon so far in lunar rocks indicates that much of the magma was probably crystallized within 100 million years of the Moon’s formation.

Chemical analysis of the meteorite NWA 7533 indicates that it may be a Martian regolith breccia and, if so, that the crust of Mars may have formed in the first 100 million years of the planet’s history.

This paper reports the discovery of micro-diamond inclusions in zircon from the Jack Hills (Western Australia), which is up to 4,252 million years old and includes the oldest known diamonds found in terrestrial rocks. The spread of ages indicates that either the conditions required for diamond formation were repeated several times during early Earth history or that there was significant recycling of ancient diamond.

Fragment #443 of the Luna 16 sample is of extra-lunar origin. It was probably delivered from an LL chondrite asteroid around 1 Gyr ago, directly as a micrometeorite or as a result of a bigger impact, and never experienced temperatures higher than 400 °C since its formation. Its characteristics are compatible with a stony parent body coming from the Flora family.

Constraints on the cratering history of the Moon from the modelled production and removal of crustal porosity by impacts are inconsistent with an extended period of bombardment.

Isotopic compositions of ancient zircons from the NWA 7034 Martian meteorite suggest that Mars must have formed its primordial crust extremely swiftly, less than 20 million years after the formation of the Solar System.