Overall
- We reproduce FT like results using a technique and a
different set of underlying assumptions. - However, not enough evidence that EQS improves
upon FT to support routine EQS deployment.
New satellite data – ESA Swarm
- Three identical satellites, each 9 m long with boom deployed, measuring the magnetic field and complementary plasma parameters
Swarm magnetic field sensors
- Absolute scalar magnetometer that can also deliver vector measurements (France)_
- Optical bench: vector field magnetometer and 3-head star camera (Denmark)
- Magnetometers mounted on boom
Launch/Comissioning
- Launched on 22 November 2013 on Rockot launcher from the Plesetsk Cosmodrome in Russia
- Breeze upper stage released the tightly packed satellites into near-polar circular orbit at an altitude of 490 km
- Final orbit configuration is two at a lower altitude, measuring the East-West gradient of the magnetic field, the third at a higher altitude in a different local time sector
Data availability
- All instruments working to specification with exception of 1 (redundant) scalar magnetic field sensor and 1 accelerometer
- Unexpected thermo-electric/thermoelastic behaviour in optical bench – very small, can be modelled '
- Global coverage of data within a few days
Data coverage 24 Oct
- Scalar
- Vector
- Local times of near-noon (UT) ascending nodes currently 08:39 for lower 2 satellites and 09:36 for higher satellite
Swarm - Science goals
- Core field dynamics
- Inner core control of outer core motion expected at poles?
- Small-scale waves in core flows
- Lithospheric field down to ~350 km wavelengths
- Deep lithospheric structure
- World digital magnetic anomaly map
- Bridging the gap to aeromag surveys
- ‘External’ magnetic fields
- Ionosphere and magnetosphere – short wavelength time/space variations
- Magnetic forcing of atmospheric density, composition
- ‘Space weather’ monitoring
- 3D mantle electrical conductivity
....
View the entire Presentation:
Recent Developments in Modelling the Internal Magnetic Field of the Earth
Susan Macmillan and Laurence Billingham