Mars generates magnetic storms at its bow shock, new data reveals
Researchers analyzed five years of data from NASA's MAVEN spacecraft and identified over 21,000 intense magnetic disturbances around Mars. The finding reshapes understanding of how planetary magnetic fields interact with solar wind and could improve predictions for future crewed missions and communication systems operating near Mars.
Originaltitel: Statistical Study of Short Large-Amplitude Magnetic Structures at Mars Observed by MAVEN
<p>We present a statistical study of Short Large-Amplitude Magnetic Structures (SLAMS) in the Martian foreshock using data from the Mars Atmosphere and Volatile Evolution (MAVEN) mission between 01 January 2015 and 31 December 2019. We have identified 21,008 SLAMS during this time interval and statistical results are presented on the SLAMS relation to upstream parameters, such as Alfvénic Mach number and angle to the bow shock normal (Formula presented.), as well as their properties, such as amplitude and temporal scale size. SLAMS are observed most frequently near the bow shock with an average Alfvén Mach number of 15.0 and an average background magnetic field of around 2.0 nT, which are close to the typical upstream bow shock conditions at Mars. The Martian SLAMS display an average temporal scale size of 2.0 s and an average relative magnetic amplitude of 2.7. They occur across a broad range of (Formula presented.) at Mars, in contrast to the predominant quasi-parallel region occurrence at Earth. This is most likely due to the proton cyclotron wave (PCW) generated by picked-up exospheric ions, which can generate quasi-periodic SLAMS in both shock regions, that is, quasi-parallel and quasi-perpendicular.</p>