The twin Van Allen Probes each carry a triaxial fluxgate magnetometer. Their orbits transverse a large of range of magnetic intensity. A procedure is described that calibrates the magnetometer in the spinning-spacecraft frame and in the presence of a persistent gradient of the magnetic field. This is done by extending a model based on a constant background magnetic field to a model with a changing magnetic field during intervals used for calibration. Model parameters derived from short intervals are obtained by direct calculation, and uncertainties are propagated throughout the analysis. A daily ensemble analysis of interval-derived parameters and uncertainties is then made to correct for sensor bias and misalignment. The whole analysis is iterated to convergence in a few steps based on the estimated uncertainties associated with the model parameters.

中文翻译：

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Van Allen探针磁力计的飞行校准

双重Van Allen探针各自带有三轴磁通门磁力计。它们的轨道横穿了很大的磁场强度范围。描述了一种在旋转的航天器框架中并且在存在持续磁场梯度的情况下校准磁力计的程序。这是通过在校准间隔期间将基于恒定背景磁场的模型扩展为磁场变化的模型来完成的。通过直接计算获得了来自短时间间隔的模型参数，并且不确定性会在整个分析过程中传播。然后对间隔参数和不确定性进行每日整体分析，以校正传感器偏差和未对准。