Analysis of quasi-steady component in acceleration measurement data obtained onboard Foton M-2

The paper presents the results of the investigation of the measurement data obtained onboard the spacecraft Foton M-2 by the triaxial accelerometer TAS3. TAS3 had a sample rate equal to 1000 readings per second and produced the data in a wide spectral range. We extracted the low-frequency component from those data and compared it with its calculation analog that was obtained by reconstruction of the spacecraft attitude motion. The spectral analysis of functions presenting the both results was done. It confirmed the influence of the Earth magnetic field upon the measurement data. When we made a correction for this influence and refined the position of the accelerometer onboard the spacecraft the results obtained in these both ways, coincided with each other very exactly (the mean-root-square error doesn't exceed 10$^{-6}$ m/s$^2$).