1 / 12

THEMIS

THEMIS. Peticolas Intro (10min) Bester Spacecraft Ops and orbits (10 min) Bonnell instrumentation (10min) Peticolas ground-based instruments and E/PO program (10min) Bonnell science (10min). THEMIS Introduction Dr. Laura Peticolas Space Sciences Laboratory, UC Berkeley.

dliston
Télécharger la présentation

THEMIS

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. THEMIS • Peticolas Intro (10min) • Bester Spacecraft Ops and orbits (10 min) • Bonnell instrumentation (10min) • Peticolas ground-based instruments and E/PO program (10min) • Bonnell science (10min) THEMIS Introduction - 1

  2. THEMIS Introduction Dr. Laura Peticolas Space Sciences Laboratory, UC Berkeley Thanks to Dr. D. Sibeck for several slides THEMIS Introduction - 2

  3. Auroras - magnificent lights in the polar sky THEMIS Introduction - 3

  4. Substorms in Aurora If you have the good fortune to watch an auroral substorm tonight you will see the aurora progress over about an hour as: • A single arc in the sky, brightening and moving towards the equator (growth phase) • Then suddenly substorm onset will occur and the arc will erupt into many quickly moving and colorful auroral filaments, spreading to fill the sky (expansion or break-up phase) • It will end with 3 second period pulsating patches of dim aurora (recovery phase) THEMIS Introduction - 4

  5. Substorms in Aurora This pattern can be seen in all-sky imagers (break-up phase seen in a UA Fairbanks camera) … and from space (shown here by Dynamics Explorer satellite in the Ultraviolet) THEMIS Introduction - 5

  6. Question 1 What causes this sudden change in the aurora at auroral onset? To answer this question, first we look at the space around Earth… THEMIS Introduction - 6

  7. Earth’s magnetic field... THEMIS Introduction - 7

  8. …shields us from the 1,000,000 mile/hr (447 km/s) solar wind THEMIS Introduction - 8

  9. …Takes a battering from the solar wind THEMIS Introduction - 9

  10. stretch magnetic field lines to the breaking point Geomagnetic substorms A B C D THEMIS Introduction - 10

  11. … causing the onset of an auroral substorm Question 2: Where did this sudden release of energy in Earth’s magnetosphere first occur? When did auroral onset begin in relation to the magnetospheric substorm onset? THEMIS Introduction - 11

  12. THEMIS • THEMIS = Time History of Events and Macroscale Interactions during Substorms • What Events? • Substorm Onset (GBO All-Sky Cameras and Mags) • Current Disruption and Redirection (THEMIS Probes) • Magnetic Reconnection (THEMIS Probes) P3,P4,P5 P2 P1 1000-1500 km/s! THEMIS Introduction - 12

More Related