Long-lived magnetism from solidification-driven convection on the pallasite parent body

@article{Bryson2015LonglivedMF,
  title={Long-lived magnetism from solidification-driven convection on the pallasite parent body},
  author={James F. J. Bryson and Claire Isobel O'Bryen Nichols and Julia Herrero‐Albillos and Florian Kronast and Takeshi Kasama and Hossein Alimadadi and G. Laan and Francis Nimmo and Richard J. Harrison},
  journal={Nature},
  year={2015},
  volume={517},
  pages={472-475}
}
Palaeomagnetic measurements of meteorites suggest that, shortly after the birth of the Solar System, the molten metallic cores of many small planetary bodies convected vigorously and were capable of generating magnetic fields. Convection on these bodies is currently thought to have been thermally driven, implying that magnetic activity would have been short-lived. Here we report a time-series palaeomagnetic record derived from nanomagnetic imaging of the Imilac and Esquel pallasite meteorites… 

Magnetic Mineralogy of Meteoritic Metal: Paleomagnetic Evidencefor Dynamo Activity on Differentiated Planetesimals

Many meteorite parent bodies experienced large-scale melting due to heating from short-lived radionuclides during the early solar system, leading to differentiation and the formation of a metallic

The Top‐Down Solidification of Iron Asteroids Driving Dynamo Evolution

The cores of some small planetesimals, such as asteroid (16) Psyche, are thought to have been exposed through collisions during the early solar system that removed their mantles. These small bodies

A Long‐Lived Planetesimal Dynamo Powered by Core Crystallization

The existence of numerous iron meteorite groups indicates that some planetesimals underwent melting that led to metal‐silicate segregation, sometimes producing metallic cores. Meteorite paleomagnetic

Magnetic meteorites and the early solar system

Today, the Earth generates a magnetic field through convection of the electrically conducting molten iron in its outer core. Core convection is governed by the thermal and chemical processes that

Meteorite cloudy zone formation as a quantitative indicator of paleomagnetic field intensities and cooling rates on planetesimals

The Thermal Evolution of Planetesimals During Accretion and Differentiation: Consequences for Dynamo Generation by Thermally‐Driven Convection

The meteorite paleomagnetic record indicates that differentiated (and potentially, partially differentiated) planetesimals generated dynamo fields in the first 5–40 Myr after the formation of
...

References

SHOWING 1-10 OF 37 REFERENCES

Magnetic evidence for a partially differentiated carbonaceous chondrite parent body

The textures of chondritic meteorites demonstrate that they are not the products of planetary melting processes. This has long been interpreted as evidence that chondrite parent bodies never

Evidence for a Dynamo in the Main Group Pallasite Parent Body

Paleointensity measurements indicate strong paleomagnetic fields, suggesting dynamo action in the pallasite parent body, and suggest that some pallasites formed when liquid FeNi from the core of an impactor was injected as dikes into the shallow mantle of a ~200-kilometer-radius protoplanet.

Paleomagnetic Records of Meteorites and Early Planetesimal Differentiation

The large-scale compositional structures of planets are primarily established during early global differentiation. Advances in analytical geochemistry, the increasing diversity of extraterrestrial

Energetics of asteroid dynamos and the role of compositional convection

The conditions under which a dynamo can operate in the core of a small planetary body or asteroid are examined. Compositional convection driven by inner core growth is thermodynamically much more

Early Lunar Magnetism

It is uncertain whether the Moon ever formed a metallic core or generated a core dynamo. The lunar crust and returned samples are magnetized, but the source of this magnetization could be meteoroid

Planetary Magnetic Fields: Achievements and Prospects

The past decade has seen a wealth of new data, mainly from the Galilean satellites and Mars, but also new information on Mercury, the Moon and asteroids (meteorites). In parallel, there have been

Origin, age, and composition of meteorites

This paper attempts to bring together and evaluate all significant evidence on the origin of meteorites.The iron meteorites seem to have formed at low pressures. Laboratory evidence shows that the