Journal article
The spinning Astrid-2 satellite used for modeling the Earth's main magnetic field
Department of Electrical Engineering, Technical University of Denmark1
Measurement and Instrumentation Systems, National Space Institute, Technical University of Denmark2
National Space Institute, Technical University of Denmark3
Solar System Physics, National Space Institute, Technical University of Denmark4
The Swedish micro-satellite Astrid-2 was successfully launched into a near polar orbit in December 1998. Despite the fact that the primary science mission was auroral research, the magnetic instrument was designed to accomplish high-resolution and high-precision vector field magnetic measurements, and therefore mapping of the Earth's magnetic field was possible.
The spacecraft spins about a highly stable axis in space. This fact and the globally distributed data make the magnetic measurements well suited for the estimate of a magnetic field model at the spacecraft altitude (about 1000 km). This paper describes the initial analysis of the Astrid-2 magnetic data.
As a result of the study of a single day (February 7, 1999), magnetically fairly quiet, it was possible to in-flight adjust the calibration of the magnetometer and find a magnetic field model fitting the scalar component of the measurements to better than 5 nT(rms) for latitudes Equatorward of 50degrees.
Several methods for field modeling are discussed in this paper under the assumption that the direction of the spin axis in inertial space is nearly constant, and this assumption is corroborated by the observations. The approximate inertial orientation of the magnetometer could then be determined simultaneously with the instrument intrinsic calibration and the estimate of main field model coefficients.
Hence, apart from the scientific use of the magnetic data, the attitude of the spacecraft may be estimated with high precision.
| Language: | English |
|---|---|
| Publisher: | IEEE |
| Year: | 2002 |
| Pages: | 898-909 |
| ISSN: | 15580644 and 01962892 |
| Types: | Journal article |
| DOI: | 10.1109/TGRS.2002.1006371 |
| ORCIDs: | Merayo, José M.G. and Brauer, Peter |
Amorphous magnetic materials calibration data models data processing geomagnetism geophysical inverse problems magnetic field measurement magnetic fields magnetometers measurement modeling satellites
1000 km AD 1999 02 07 Astrid-2 Calibration Earth Geoscience Instruments Magnetic field measurement Magnetic variables measurement Magnetometers Satellites Space vehicles Spinning artificial satellite artificial satellites geophysical measurement technique geophysical techniques magnetic field magnetic instrument main field mapping'of polar orbit rotating satellite scalar component spinning satellite vector field
