[Editor’s note: From a paper by Benoit Langlais and four co-authors recently published in the Journal of Geophysical Research.]
A New Model of the Crustal Magnetic Field of Mars Using MGS and MAVEN
• MGS and MAVEN magnetic field measurements are combined into a high‐resolution magnetic field model
• The new model extends up to SH degree 134, corresponding to 160‐km horizontal resolution at the Martian surface
• It enables local studies, where geologic and magnetic features can be compared
While devoid of an active magnetic dynamo field today, Mars possesses a remanent magnetic field that may reach several thousand nanoteslas locally. The exact origin and the events that have shaped the crustal magnetization remain largely enigmatic.
Three magnetic field data sets from two spacecraft collected over 13 cumulative years have sampled the Martian magnetic field over a range of altitudes from 90 up to 6,000 km: (a) Mars Global Surveyor (MGS) magnetometer (1997–2006), (b) MGS Electron Reflectometer (1999–2006), and (c) Mars Atmosphere and Volatile EvolutioN (MAVEN) magnetometer (2014 to today).
In this paper we combine these complementary data sets for the first time to build a new model of the Martian internal magnetic field. This new model improves upon previous ones in several aspects: comprehensive data coverage, refined data selection scheme, modified modeling scheme, discrete‐to‐continuous transformation of the model, and increased model resolution.
The new model has a spatial resolution of ∼160 km at the surface, corresponding to spherical harmonic degree 134. It shows small scales and well‐defined features, which can now be associated with geological signatures. [More at link]