1. The most challenging consequences of Earth’s space environment occur in the inner radiation belt
So far you have been hearing about sensational new results regarding the outer (mostly) electron belts shown here in violet colors.
We now look at the Earth’s inner radiation belt (mostly protons), shown in green
Cover: Dynamics of the Earth's Radiation Belts and Inner Magnetosphere
Editors: Danny Summers, Ian Mann, Daniel Baker, and Michael Schulz

2. Models exist for this inner belt but are known to have tremendous uncertainties
Current inner belt models are based on dated measurements (obtained using old technologies) and therefore are not accurate enough for today’s space weather needs
As an example, it is not yet known how high the energy of the protons can reach in the heart of this inner belt.
McIlwain 1963
Sawyer & Vette 1976

3. With the Van Allen Probes we can now map out spatial distributions of the inner (and outer) belts with high fidelity.
Shown here are data from the ECT/REPT instrument from spacecrafts A & B in the form of Proton Fluxes taken during the inbound pass

4. 1 billion electron volts
For the first time, we have accurate measures within the heart of the inner belt of proton energies as high as 1 billion electron volts
PRELIMINARY
1 billion electron volts
Accurate spectra measuring the extent of the inner belt within the core regions up to1 billion electron volts

5. Why do we care? Major Space Environment Hazards
False stars in star tracker CCDs
During exposure to multi-MeV protons
Before
After
Before
Solar array power decrease due to radiation damage
Surface degradation from radiation
Single event effects in microelectronics
Electronics degrade due to total radiation dose
1101  0101
Solar array arc discharge
Spacecraft components become radioactive
Electromagnetic pulse from vehicle discharge
(on surface, behind thin shielding, or deep inside)
Induced
Voltage
Time

6. Why do we care? Operational Space Environment Hazards1 10
100
1000 50
Van Allen Probes
SAMPEX LICA
Charging Events
L ~ Equatorial Radial Distance (RE)
HEO
GPS
CRRES MEP-SEU Anomalies
CRRES VTCW Anomalies
Inner
Belt
Slot
Outer Belt 5 15 2 3 4 6 7 8
SEUs
Internal
Charging
Surface
(Dose behind 82.5 mils Al)
Plasma Sheet
Magnetic Latitude in LEO (deg) 45 55 60 63 66 68 69
GEO
A staggering number of the spacecraft we rely upon daily have to spend a part of their orbit in the harshest of Earth’s radiation environment