the space radiation envoronment as it relates to …counts/cm 2 /s/ster/mev nt proton fluxes –...

AAS GNC Conference in Breckenridge, CO – Space Radiation Environment presented by Kenneth A. LaBel– Feb 8, 2005 1

The Space Radiation Environment as It Relates to Electronic System

Performance:Or Why Not to Fly Consumer Electronics

Components in SpaceJanet L. Barth, Michael A. Xapsos,

Kenneth A. LaBel, NASA/[email protected]

Co-Manager, NASA Electronic Parts and Packaging (NEPP) ProgramGroup Leader, Radiation Effects and Analysis Group (REAG), NASA/GSFC

Project Technologist, Living With a Star (LWS) Space Environment Testbeds (SET)

Christian Poivey, SGT Corp* (now with MEI)

This presentation is supported by the NASA Electronic Parts and Packaging (NEPP) Program


Outline

• The Space Radiation Environment Overview

• The Environment in Action– Solar Event from 2003

• Real Estate– Location and Timing

• Engineering Models• Final Remark


The NATURAL Space Radiation Environment

STARFISH detonation –Nuclear attacks are not considered in this presentation


Space Environments and Related Effects

Plasma

Charging ImpactsDrag SurfaceErosion

Ultraviolet & X-ray

Neutralgas particles

Particleradiation

Micro-meteoroids & orbital debris

Ionizing &Non-Ionizing

Dose

•Degradation of micro-

•electronics•Degradation

of optical components•Degradation of solar cells

SingleEvent

Effects

•Data corruption•Noise on

Images•System

shutdowns•Circuit damage

•Degradation of thermal, electrical,

optical properties

•Degradation of structural

integrity

•Biasing of instrument readings•Pulsing•Power drains

•Physical damage

•Torques•Orbital decay

•Structural damage

•Decompression

Space Radiation Effectsafter Barth


What is the Space Radiation Environment Hazard?

• Energetic particles– Protons. Electrons, Heavy ions (ex., charged Fe ion)

• Particles can come from the Sun– Ex., Solar events

• Particles can be “trapped”– Located within a magnetic field

• Ex., Van Allen Belts• Particles can come from somewhere else in the galaxy

– Ex., Galactic Cosmic Rays (GCRs) – Heavy Ions of “unknown” origin

• Sun (solar cycle) acts as modulator for environment


Near-Earth Space Radiation Environment

Trapped ParticlesProtons, Electrons, Heavy Ions

afterNikkei Science, Inc.

of Japan, by K. Endo

Galactic Cosmic Rays (GCRs)

Solar Protons&

Heavier Ions

Deep-space missions may also see: neutrons from planetarybackground, nuclear source or other trapped particle belts

Atmosphere and terrestrial may see GCR and secondary particles

Earth


Solar Particle Events

• Cyclical (Solar Max, Solar Min)– 11-year AVERAGE (9 to 13)– Solar Max is more active time period

• Two types of events– Gradual (Coronal Mass Ejections –

CMEs)• Proton rich

– Impulsive (Solar Flares)• Heavy ion rich

• Abundances Dependent on Radial Distance from Sun

• Particles are Partially Ionized– Greater Ability to Penetrate

Magnetosphere than GCRs• Also generates neutrons in the

atmosphere

Holloman AFB/SOON


Sunspot Cycle:An Indicator of the Solar Cycle

Length Varies from 9 - 13 Years7 Years Solar Maximum, 4 Years Solar Minimum

1947 1997Years0

50

150

200

250

100

300

Suns

pot N

umbe

rs

Cycle 18

Cycle 22Cycle 21Cycle 20Cycle 19

after Lund Observatory


Solar Proton Event - October 1989

1 0 -4

1 0 -3

1 0 -2

1 0 -1

1 0 0

1 0 1

1 0 2

1 0 3

1 0 4

1 0 5

1 51 6

1 71 8

1 92 0

2 12 2

2 32 4

2 52 6

2 72 8

2 93 0

3 11

23

45

67

89

1 01 1

1 21 3

1 41 5

-2 0 00

2 0 0

O c to b e r N o ve m b e r

Cou

nts/

cm2 /s

/ste

r/MeV

nTProton Fluxes – “99% Worst Case Event”

GOES Space Environment Monitor


Free-Space Particles: Galactic Cosmic Rays (GCRs) or Heavy

Ions• Definition

– A GCR ion is a charged particle (H, He, Fe, etc)

– Typically found in free space (galactic cosmic rays or GCRs)

• Energies range from MeV to GeVs for particles of concern for SEE

• Origin is unknown– Important attribute for impact

on electronics is how much energy is deposited by this particle as it passes through a semiconductor material. This is known as Linear Energy Transfer or LET (dE/dX).

10-1 100 101 10210-810-710-610-510-410-310-210-1100101102103104

GEOGTOMEOEOSLEO

Z = 2 - 92

LET

Flue

nce

(#/c

m2 /d

ay)

LET (MeV-cm2/mg)

CREME 96, Solar Minimum, 100 mils (2.54 mm) Al

Commercial Technology SensitivityTime


Trapped Particles in the Earth’s Magnetic Field: Proton & Electron Populations

1 2 3 4 5 6 7 8 9 101234

L-Shell

AP-8 Proton Model AE-8 Electron Model

Ep > 10 MeV Ee > 1 MeV

#/cm2/sec #/cm2/sec

A dip in the earth’s dipole moment causes an asymmetry in the picture above:The South Atlantic Anomaly (SAA)

Geomagnetic cutoff implies some shielding protection from GCR and solar particles

Earth


SAA and Trapped Protons:SRAM Upset Rates by Altitude Slices on CRUX/APEX

-1 8 0 -1 5 0 -1 2 0 -9 0 -6 0 -3 0 0 3 0 6 0 9 0 1 2 0 1 5 0 1 8 0

L o n g itu d e

-9 0

-7 5

-6 0

-4 5

-3 0

-1 5

0

1 5

3 0

4 5

6 0

7 5

9 0

Latit

ude

H ita c h i 1 M :A lt itu d e :1 2 5 0 k m - 1 3 5 0 k m

1 .0 E -7 to 5 .0 E -75 .0 E -7 to 1 .0 E -61 .0 E -6 to 5 .0 E -65 .0 E -6 to 1 .0 E -51 .0 E -5 to 5 .0 E -55 .0 E -5 to 1 .0 E -41 .0 E -4 to 5 .0 E -45 .0 E -4 to 1 .0 E -31 .0 E -3 to 5 .0 E -3

U p s e ts /B it /D a y

-1 8 0 -1 5 0 -1 2 0 -9 0 -6 0 -3 0 0 3 0 6 0 9 0 1 2 0 1 5 0 1 8 0

L o n g itu d e

-9 0

-7 5

-6 0

-4 5

-3 0

-1 5

0

1 5

3 0

4 5

6 0

7 5

9 0

Latit

ude

H ita ch i 1 M :A ltitu d e :6 5 0 k m - 7 5 0 km


U p se ts /B it/D a y

-1 8 0 -1 5 0 -1 2 0 -9 0 -6 0 -3 0 0 3 0 6 0 9 0 1 2 0 1 5 0 1 8 0

L o n g itu d e

-9 0

-7 5

-6 0

-4 5

-3 0

-1 5

0

1 5

3 0

4 5

6 0

7 5

9 0

Latit

ude

H ita c h i 1 M :A lt i tu d e :1 7 5 0 k m - 1 8 5 0 k m



-1 8 0 -1 5 0 -1 2 0 -9 0 -6 0 -3 0 0 3 0 6 0 9 0 1 2 0 1 5 0 1 8 0

L o n g itu d e

-9 0

-7 5

-6 0

-4 5

-3 0

-1 5

0

1 5

3 0

4 5

6 0

7 5

9 0

Latit

ude

H ita c h i 1 M :A lt i tu d e :2 4 5 0 k m - 2 5 5 0 k m




Solar Cycle Effects:Modulator and Source

• Solar Maximum– Trapped Proton Levels Lower,

Electrons Higher– GCR Levels Lower– Neutron Levels in the Atmosphere

Are Lower– Solar Events More Frequent &

Greater Intensity– Magnetic Storms More Frequent --

> Can Increase Particle Levels in Belts

• Solar Minimum– Trapped Protons Higher, Electrons

Lower– GCR Levels Higher– Neutron Levels in the Atmosphere

Are Higher– Solar Events Are Rare

Light bulb shaped CMEcourtesy of SOHO/LASCO C3 Instrument


The Environment in Action

“There’s a little black spot on the sun today”


Recent Solar Events –A Few Notes and Implications

• In Oct-Nov of 2003, a series of X-class (X-45!) solar events took place– High particle fluxes were noted– Many spacecraft performed safing maneuvers– Many systems experienced higher than normal (but correctable) data error rates– Several spacecraft had anomalies causing spacecraft safing– Increased noise seen in many instruments– Drag and heating issues noted– Instrument FAILURES occurred– Two known spacecraft FAILURES occurred

• Power grid systems affected, communication systems affected…

Proton fluxes during“Halloween Event”


SOHO LASCO C2 of the Halloween Solar Event of 2003

To run this video see http://radhome.gsfc.nasa.gov/radhome/papers/c2_SOHO.mpg


GOES SXI View of the Halloween Event

To run this video see http://radhome.gsfc.nasa.gov/radhome/papers/GOES_SXI_SPEC.mpeg


Solar Event Effect - Solar Array Power Output Degradation on CLUSTER Spacecraft

Many other spacecraft tonoted similar degradation

as well.


Selected Other Consequences

• Orbits affected on several spacecraft

• Power system failure– Malmo, Sweden

• High Current in power transmission lines– Wisconsin and New York

• Communication noise increase• FAA issued a radiation dose

alert for planes flying over 25,000 ft

A NASA-builtradiation monitor

that can aidanomaly resolution,lifetime degradation,protection alerts, etc.

Important note:Effects propagated to

terrestrial levels


Real Estate: Location and Timing Drive Radiation Exposure

• Location– Where you fly and the route you take to get there impacts the

levels of radiation exposure• GEO, LEO, Lunar, Mars, Jovian all have vastly different exposure

levels– Where your system is within a spacecraft affects the hazard

• Shielding plays a role in reducing some radiation exposure (but not a panacea!)

• Timing– Two issues impact exposure levels

• When you fly– Activity level of environment

• How long you fly– Cumulative exposure levels and activity level

• Two examples to follow– LEO (Hubble), Lunar


LEO Radiation EnvironmentLow Inclination

• Pros– Fly below the earth’s

magnetic belts– Limited direct exposure to

GCR and solar particles– Relatively low levels of

particles for longer-term damage

• Assumes location inside the spacecraft

• Cons– Exposure to trapped particles

in SAA• Protons can induce noise or

upsets in commercial and non-radiation hardened devices

• Optics systems must also be concerned with trapped electrons

– Some GCR and solar particles may penetrate

• Secondaries

Sample particle interaction ofa 100 MeV proton in a 5um Si

block using the GEANT4 toolkit.

after Weller, 2004

p


Lunar Environment

• Pros– No trapped particles

• Low “quiet” day particle levels

– Low level, low energy neutrons

• Created from GCR interaction with the lunar atmosphere/surface

• Cons– Full exposure to GCR

• Can be destructive to commercial electronics

– Full exposure to solar particles

• Long-term and transient effects issues

Lunar footprintCourtesy of

NASA archives

LunarscapeCourtesy of

JPL Photojournal Archive


Radiation Environment Models• Trapped particles (Earth)

– NASA standard is AP-8 (proton) and AE-8 (electron)• One model for Solar Max, one for Solar Min• These are static averages of old data

– Updates being worked based on newer data, statistics, etc• Boeing TPM (Trapped Proton Model)-1 based on NOAA/TIROS and

CRRES data• ONERA-LANL POLE model for GEO electrons

• Trapped Particles (Jovian)– Original model from the 1980’s: Divine model (proton and

electrons)• Update based on Galileo data: Galileo Interim Radiation Electron

(GIRE) Model • Solar Particles

– NASA PSYCHIC model for solar protons and heavy ions• GCR

– NRL CREME96 model– NASA Badhwar and O’Neill model


Final Remark• Beyond the “standard” concerns of space radiation

environment for electronics/optics, solar magnetic storms impact needs to be considered

– Presentation available NLT 2-14-05 at http:/radhome.gsfc.nasa.gov

To run this video see http://radhome.gsfc.nasa.gov/radhome/papers/storm.avi

the space radiation envoronment as it relates to …counts/cm 2 /s/ster/mev nt proton fluxes –...

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