earth s radiation belt
Download
Skip this Video
Download Presentation
Earth’s Radiation Belt

Loading in 2 Seconds...

play fullscreen
1 / 31

Earth’s Radiation Belt - PowerPoint PPT Presentation


  • 109 Views
  • Uploaded on

Space Plasma Physics. Earth’s Radiation Belt. Xi Shao Department of Astronomy, University Of Maryland, College Park, MD 20742. Space Plasma Physics. Outline. History and importance of studying Earth’s radiation belt Dynamics of Earth’s radiation belt: Observations

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about ' Earth’s Radiation Belt' - ataret


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.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
earth s radiation belt

Space Plasma Physics

Earth’s Radiation Belt

Xi Shao

Department of Astronomy,

University Of Maryland, College Park, MD 20742

outline

Space Plasma Physics

Outline
  • History and importance of studying Earth’s radiation belt
  • Dynamics of Earth’s radiation belt: Observations
  • Origin of Earth’s radiation belt: Geomagnetic Storms and Substorms.
  • Modeling formation of Earth’s radiation belt.
  • Slot Region formation.
slide3

Radiation Belts: The Big Picture

Explorer I

Space Plasma Physics

  • The Radiation Belt is a energetic torus of energetic charged particles (plasma) around Earth, held in place by Earth\'s magnetic field
  • Historic discovery in 1958 by the Explorer I in 1958, and Explorer III missions, under Dr.James Van Allen at the University of Iowa.
  • The trapped radiation was first mapped out by Sputnik 3, Explorer IV, Pioneer III and Luna 1.
  • Energetic electrons form two distinct radiation belts, while protons form a single belt.
slide4

The Radiation Belts Today:

a Dynamic Space Weather Environment

  • Space Weather Applications:
  • Astronauts safety
  • Hardware integrity
  • Mission performance
    • Satellite solar cell panel degradation
    • Single Event Upset (SEU)
slide5

The Radiation Belts Today:

a Dynamic Space Weather Environment

why trapped
Why Trapped?

Proton Orbit

Electron Orbit

slide7

NOAA POES Observations-Dynamical View

Orbit Altitude:

~ 800 km

Inclination:

~ 98 degree

Orbit Period:

~100 mins

MEPED Detector Energy Channels

used in this poster:

Proton: >80 MeV

(Omni-Detector)

Electron: > 300 keV

(Omni-Directional flux derived from 2 telescopes)

NOAA POES Data obtained from

http://poes.ngdc.noaa.gov

slide9

Electron (> 300 keV) Belt Dynamics

(1979-1991)

Outer Belt

Weakens

Mar. 1991

Mar. 1989

Feb. 1986

Jul. 1982

Apr. 1981

Inner belt

Enhanced

slide10

Electron (> 300 keV) Belt Dynamics

(1992-2004)

Outer Belt

Weakens

Oct-Nov, 2003

Inner belt

Re-Enhanced

NOAA-15 changes telescope pointing direction and data is still in processing for L < 2.

slide12

Proton (> 80 MeV) Belt Dynamics

(1979-1991)

Mar. 1991

Mar. 1989

Feb. 1986

slide13

Proton (> 80 MeV) Belt Dynamics

(1992-2004)

Oct-Nov, 2003

slide15

Space Plasma Physics

Modeling Solar Wind Interaction with Earth’s Magnetosphere

MHD Equations Solved on a 3D Stretched Spherical Mesh

slide19

Space Plasma Physics

  • Magnetospheric Substorm
slide20

Mid-Tail Reconnection

t= 00:-07:-48

t= 00:47:20

t= 00:51:05

t= 00:56:06

t= 01:01:07

t= 01:06:08

slide22

Space Plasma Physics

Ring Current Development

1:00 UT

slide23

Space Plasma Physics

Physical Modeling of Radiation Belt

3D Electric-Magnetic

field from LFM Global

MHD Model of

Earth’s Magnetosphere

Initial Test Particle

Distribution

3D Particle Tracing

Code (Full Motion for

Protons, and Guiding

Center for electrons)

e

RB energetic

particle distribution

p

slide26

Energization of Radiation Belt Electrons

Initial Configuration of 5keV electrons

A snapshot of electron location and energy in 3D10 mins later

formation of slot region in electron radiation belt
Formation of Slot Region in Electron Radiation Belt

Whistler Waves in the

Plasmasphere

Slot Region

summary
Summary
  • Review History and Importance of Radiation Belt
  • Radiation Belt Structure
  • Origin of Radiation Belt
  • Radiation Belt Slot region
  • Safe-zone Solar-Cycle Shifting.
outstanding science questions
Outstanding science questions
  • Acceleration mechanisms;
  • their relative significance
  • Solar wind-inner magnetosphere coupling
  • Loss mechanisms
  • User needs a Model:
  • Accurate flux models
  • L shell specificity
  • Forensic evaluation
  • Nowcasting
ad