Planetary magnetic fields beyond Earth
Mercury, Ganymede and the giant planets make magnetic fields with a dynamo (flowing electrically conducting fluid deep inside that generates and sustains a field), and the Moon and Mars once did, but several of these fields do not fit simple theory. Saturn's field is too symmetric, Mercury's too weak, and the young Moon's too strong.
Why it matters
Planetary fields constrain deep interiors that cannot be sampled any other way.
Review
G. Schubert, K. M. Soderlund, Planetary magnetic fields: Observations and models, Physics of the Earth and Planetary Interiors, 2011. https://doi.org/10.1016/j.pepi.2011.05.013 reference checked
Timestamp record
- Signed record
- d630b91b3d15…
- Public log
- Entry 205, in checkpoint 2,123
- In the log by
- Block 969,698, 2026-10-03
This text was in the PubPhys log by that date. The date says nothing about when the problem was first posed.