Extended Data Fig. 1: Virtual spacecraft observations near the bow shock.
From: Transmission of foreshock waves through Earth’s bow shock
From top to bottom: (a) magnetic field strength (black) and ion density (red), (b) magnetic field components, (c) wavelet power spectrum of the magnetic field strength, and (d) cross-correlation of the magnetic field strength and density fluctuations. The pink dashed line in panel d shows the predicted foreshock wave period using the Takahashi et al.9 formula. The black contours in panels c and d delineate the 95% confidence interval of the wavelet power spectrum. The virtual spacecraft is positioned in (x = 9.6 RE; y = 0 RE) and is initially located in the foreshock, then crosses the shock shortly after t = 400 s and remains in the magnetosheath afterwards, due to the outward bow shock motion. Between t = 400 − 450 s, fast-mode oscillations at the foreshock wave period are observed just downstream of the shock, consistent with the observations reported by Liu et al.7.
