PROBLEMS OF GEOCOSMOS

Proceedings of the 7th International Conference "Problems of Geocosmos" (St. Petersburg, Russia, 26-30 May 2008)
that difference model and real magnetosphere are of the same order.
Figure 2. Testing the synthetic data set. Comparison of Bx magnetic field component at THEMIS
spacecraft p1, p2, p3, p5 taken as input for solving the inverse problem (thin line) with its values
reconstructed using the tuned model. Periods of time marked with grey indicate SC apogee.
b. Example of routine procession of the real data. Figure 3 represents results of routine procession of real
THEMIS data we performed at January-March 2008. AE index and spacecraft footpoints latitude (in
corrected geomagnetic coordinates) are shown for 2 nd
and 6 th of February 2008. Red line corresponds to
latitude obtained from tuned model, blue – standard one, based on solar wind data. Gaps in data correspond
to periods when spacecraft was near perigee, out of magnetosphere or total function weight was smaller than
3. As one can see latitude difference is much bigger and it strongly fluctuates during disturbed day.
Figure 3. Mapping results examples. Disturbed (on the left hand side) and quiet (on the right hand side)
days are shown. Grey boxes show low-weight regions. Gaps in data may be caused by spacecraft position.
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