Mercury’s magnetic field is puzzling because it is weaker than expected for an active dynamo source, but can’t be easily explained via any other mechanism. Data from the MESSENGER mission also demonstrated that Mercury has a relatively large quadrupolar field (manifested as a large northward offset of the magnetic dipole equator) and that the large scale field is very axisymmetric.

My group and collaborators have worked on testing different mechanisms to explain Mercury’s enigmatic magnetic field using dynamo simulations. Some relevant papers include:

• Hauck II, S.A., Grott, M., Byrne, P.K., Denevi, B.W., Stanley, S., & McCoy, T.J., Mercury’s Global Evolution, in Mercury after the MESSENGER mission, ed. Solomon, S.C., Nittler, L. & Anderson, B.J. Cambridge University Press, 516-543 (2018).

• Tian, Z., Zuber, M.T. and Stanley, S., “Magnetic field modelling for Mercury using dynamo models with stable layers and laterally variable heat flux”, Icarus 260, 263-268 (2015).

• Vilim, R., Stanley, S., Hauck, S.A., Iron snow zones as a mechanism for generating Mercury’s weak observed magnetic field, J. Geophys. Res. 115, E11003 (2010).

• Zuber, M.T., Aharonson, O., Aurnou, J.M., Cheng, A.F., Hauck, S.A., Heimpel, M.H., Neumann, G.A., Peale, S.J., Phillips, R.J., Smith, D.E., Solomon, S.C., Stanley, S., The Geophysics of Mercury: Current Status and Anticipated Insights from the MESSENGER Mission, Space Science Rev., 131, 105-132 (2007).

• Stanley, S., Bloxham, J., Hutchison, W. E. and Zuber, M.T., Thin shell dynamo models consistent with Mercury’s weak surface magnetic field, Earth Planet. Sci. Lett., 234, 27-38 (2005).