A 3D representation of the location of Mars bow shock crossings when measurements were made with the Mars Express Analyser of Space Plasma and EneRgetic Atoms (ASPERA-3) Electron Spectrometer (ELS).

A team of European scientists investigated how and why the bow shock's location varies during the Martian year. They analysed more than five Martian years of measurements to identify 11,861 bow shock crossings. This is the first analysis of the bow shock to be based on data obtained over such a prolonged period and during all Martian seasons.

The results are reported in Annual variations in the Martian bow shock location as observed by the Mars Express mission, by B.E.S. Hall et al., Journal of Geophysical Research: Space Physics. 121, 2016; doi: 10.1002/2016JA023316.