Swarm a Constellation to study the Dynamics of the Earth's magnetic Field and its Interactions with the Earth System
Abstract
Magnetic fields play an important role in physical processes throughout the Universe. In our own solar system the planetary magnetic fields are surprisingly different, even for planets of similar composition. In addition to being evidence of the evolution of the planet the magnetic field exerts a very direct control of the electrodynamic environment, on thermospheric dynamics, and possibly even on the evolution of the lower atmosphere. Over the last 150 years, the axial dipole component of the Earth's magnetic field has decayed by nearly 10%. The objective of the swarm mission is to provide the best survey ever of the geomagnetic field and its temporal evolution. The magnetic field measured at or near the surface of the Earth is the superposition of contributions from a variety of sources. The scientific challenge is the sophisticated separation of these various sources and the accurate determination of the spatial and temporal structure of them all. A proposal with exactly this aim was submitted to ESA’s Earth Explorer Opportunity Mission programme and has been selected for an industrial Phase A Study to be conducted during 2003. The swarm concept consists of a constellation of four satellites in two different polar low altitude orbits. Each satellite will provide high-precision and high-resolution measurements of the vector magnetic field. A few additional instruments like GPS receivers, an accelerometer, and an electric field instrument provide supplementary information for studying the interaction of the magnetic field with other physical quantities describing the Earth system. The mission will enable investigations of the global dynamics of the fluid core, improved knowledge of the conductivity structure of the mantle and, for the first time, an unambiguous characterization of the lithospheric magnetic field in the polar regions. The geomagnetic field models flowing from this mission have practical applications in many different areas such as Space Weather and radiation hazards and the understanding of atmospheric processes related to climate and weather.
- Publication:
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EGS - AGU - EUG Joint Assembly
- Pub Date:
- April 2003
- Bibcode:
- 2003EAEJA.....4248F