Abstract:
The F-region currents are generally weak and difficult to detect. However, their contributions to the earth’s magnetic field
variations are significant and cannot be ignored by the field modelers. CHAMP satellite has therefore provided a perfect
opportunity to investigate the in-situ F-region currents on the night side of the equatorial region. The magnitudes of the
current along all the three components of the earth’s magnetic field (X, Y, Z) are investigated. However in this paper, we
present only the results on the Y-component where interesting magnetic residuals were observed. The X and Z-components
were rather masked in much noise and would require further filtering. The currents appear in both the pre-midnight and postmidnight
sectors and are spatially confined to the equatorial region bounded by the Appleton anomaly. The magnetic
residuals are generally observed in the northern hemisphere of an order of 0.8nT, which gives a height-integrated current
density of about 1.3mA/m.
