THEMIS Update and a Review of the Science Behind Magnetometer Signatures By Laura Peticolas 2. Outline 3. Satellites Update 4. Ground-based Update 5. Earth’s magnetic fields 6. Magnetic Field Strength 7. Coordinate Systems 8. Geomagnetic (GEONS) 9. Compass-type (HDZ) 10. The GEONS Data 11. Earth’s Magnetic Field 12. Different Latitudes 13. Magnetosphere 14. Magnetosphere currents 15. Solar Wind (SW) 16. Effects of Ring Current on the Mag Data 17. Auroral Currents 18. Magnetic signatures of auroral substorms 19. Kp Index 20. Kp Index = 1 21. Kp Index = 7 22. Space Weather Effects 23. Storm and Substorms 24. THEMIS will determine which competing model is correct 25. Daytime (Sq) Currents 26. Ionosphere Effects     Magnetic Field Strength • The strength of a magnetic field is the magnetic flux density, B. • The units of magnetic flux density is the Tesla or the Gauss • 1 Tesla (T) = 104 Gauss (G) • The most powerful magnets in the world are superconducting electromagnets. These magnets have magnetic fields of around 20 T. In 2003, the National High Magnetic Field Laboratory in Florida set the world record for high temperature superconducting magnets at 25 T. B • Earth’s magnetic field is 0.000 052T = 52,000 nanotesla (nT) = 0.5 gauss (G) • 1 nanotesla = 10-9 T • Changes in Earth’s magnetic field are typically 5-100 nT Slide 6 of 26