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MIT Lincoln Laboratory2001 Space Control Conf. -1RLL 4/3/2001
Operational Impacts of Space Weather
R. Lambour, A. J. Coster, R. Clouser, L. E. Thornton, J. Sharma, and A. Cott
MIT Lincoln Laboratory
2001 Space Control Conference
3 April 2001
MIT Lincoln Laboratory2001 Space Control Conf. -2RLL 4/3/2001
Outline
• Introduction – Space Weather
• Effects on Space-Based Systems
• Effects on Ground-Based systems
• Conclusions
MIT Lincoln Laboratory2001 Space Control Conf. -3RLL 4/3/2001
Space Weather
• Definition:– “Conditions on the Sun and in the solar wind, magnetosphere,
ionosphere, and thermosphere that can affect performanceand reliability of space-based and ground-basedtechnological systems.”*
*
MIT Lincoln Laboratory2001 Space Control Conf. -4RLL 4/3/2001
Effects of Space Weather on Earth
Solar Flare of 14 July 2000 Biggest Solar Storm in
Nine Years
Caused very largemagnetic storm andionospheric effects
SOHO – Solar Flare SOHO – Coronal Mass Ejection
MIT Lincoln Laboratory2001 Space Control Conf. -4RLL 4/3/2001
Effects of Space Weather on Earth
Solar Flare of 14 July 2000 Biggest Solar Storm in
Nine Years
Caused very largemagnetic storm andionospheric effects
SOHO – Solar Flare SOHO – Coronal Mass Ejection
MIT Lincoln Laboratory2001 Space Control Conf. -4RLL 4/3/2001
Effects of Space Weather on Earth
Solar Flare of 14 July 2000 Biggest Solar Storm in
Nine Years
Caused very largemagnetic storm andionospheric effects
SOHO – Solar Flare SOHO – Coronal Mass Ejection
Near peak of 11 Year solar cycle
Activity on Sun, magnetosphere and ionosphere will be amaximum for the next 2-3 years
MIT Lincoln Laboratory2001 Space Control Conf. -5RLL 4/3/2001
Outline
• Introduction – Space Weather
• Effects on Space-Based Systems– Space-Based Visible sensor
South Atlantic Anomaly Transient effects Long-term (?) effects
• Effects on Ground-Based systems
• Conclusions
MIT Lincoln Laboratory2001 Space Control Conf. -6RLL 4/3/2001
SBV Sensor
• 15 cm high straylightrejection telescope
• 4 - 420x420 LincolnLaboratory CCD
• 1.4 x 1.4 deg field of viewper CCD
• Staring sensor
MIT Lincoln Laboratory2001 Space Control Conf. -6RLL 4/3/2001
SBV Sensor
• 15 cm high straylightrejection telescope
• 4 - 420x420 LincolnLaboratory CCD
• 1.4 x 1.4 deg field of viewper CCD
• Staring sensor
• Target and star detection• Clutter rejection• Data compression
MIT Lincoln Laboratory2001 Space Control Conf. -7RLL 4/3/2001
Space Environment Effects on SBV
MIT Lincoln Laboratory2001 Space Control Conf. -8RLL 4/3/2001
South Atlantic Anomaly (SAA)
Energetic particle enhancementat low altitudes due to offset of
magnetic field
SAA
Flux contours of E > 50 MeV Protons at 500 km
MIT Lincoln Laboratory2001 Space Control Conf. -9RLL 4/3/2001
SAA Effects on SBV
Protons with energy > 10 MeV affect SBV focal planeand inhibit ability to observe valid target streaks
MIT Lincoln Laboratory2001 Space Control Conf. -10RLL 4/3/2001
Transient Effects: 14 July 2000 SolarProton Event
NOAA Geosynchronous Space Environment Summary
Solar Proton Arrival
MIT Lincoln Laboratory2001 Space Control Conf. -11RLL 4/3/2001
Transient Effects: 14 July 2000 SolarProton Event
• Solar flare occurred atend of pinch pointCONOPS testing
• One DCE produced nodata (day 197)
• Decrease in validstreaks over polarregions seen
• Decrease notattributable toanomalies
Day of Year 2000190 192 194 196 198 200
Valid
Str
eaks
per
Fra
mes
et
0.0
0.5
1.0
1.5
2.0
|Latitude| < 60|Latitude| > 60FlareStorm
MIT Lincoln Laboratory2001 Space Control Conf. -12RLL 4/3/2001
Transient Effects: 14 July 2000 SolarProton Event
• False streaks perframeset increasedsignificantly aftersolar flare
Day of Year 2000190 192 194 196 198 200
Fals
e St
reak
s pe
r Fra
mes
et
0.0
0.5
1.0
1.5
2.0 |Latitude| > 60|Latitude| < 60FlareStorm
MIT Lincoln Laboratory2001 Space Control Conf. -12RLL 4/3/2001
Transient Effects: 14 July 2000 SolarProton Event
• False streaks perframeset increasedsignificantly aftersolar flare
Day of Year 2000190 192 194 196 198 200
Fals
e St
reak
s pe
r Fra
mes
et
0.0
0.5
1.0
1.5
2.0 |Latitude| > 60|Latitude| < 60FlareStorm
Influx of solar protons over poles degraded SBV performance
MIT Lincoln Laboratory2001 Space Control Conf. -13RLL 4/3/2001
Long Term (?) Space EnvironmentEffects
SAA
MIT Lincoln Laboratory2001 Space Control Conf. -13RLL 4/3/2001
Long Term (?) Space EnvironmentEffects
SAA
MIT Lincoln Laboratory2001 Space Control Conf. -13RLL 4/3/2001
Long Term (?) Space EnvironmentEffects
SAA
• Area with reduced detections south of SAA noticed in 1998-1999
• Effect investigated by looking geographic distribution of validand false streaks
MIT Lincoln Laboratory2001 Space Control Conf. -14RLL 4/3/2001
Long Term (?) Space EnvironmentEffects
SAA
Region of interest
MIT Lincoln Laboratory2001 Space Control Conf. -14RLL 4/3/2001
Long Term (?) Space EnvironmentEffects
SAA
Region of interest
Area of degraded performance persists into 2000
MIT Lincoln Laboratory2001 Space Control Conf. -15RLL 4/3/2001
Energetic Particle Source Regions
• NOAA baseline plots show increase in trapped outer-zoneprotons south of SAA in recent years
• Consistent with location of degraded SBV performance
> 6900 keV proton data from NOAA POES MEPED sensor
90°°°°-detector0°°°°-detector
SAATrapped Protons
**SEM-2 system
MIT Lincoln Laboratory2001 Space Control Conf. -16RLL 4/3/2001
Outline
• Introduction – Space Weather
• Effects on Space-Based systems
• Effects on Ground-Based systems– Range Delay– Scintillation
– July 14-15th storm
• Conclusions
MIT Lincoln Laboratory2001 Space Control Conf. -17RLL 4/3/2001
2m2
MIT Lincoln Laboratory2001 Space Control Conf. -18RLL 4/3/2001
Illustration of Atmospheric Effects
Range Delay
2ionosphere 1 fANn e−≈
∆R metersf
N drion e
R( )
. = ∫
40 32 0
MIT Lincoln Laboratory2001 Space Control Conf. -18RLL 4/3/2001
Illustration of Atmospheric Effects
Range Delay
2ionosphere 1 fANn e−≈
∆R metersf
N drion e
R( )
. = ∫
40 32 0
Range Delay S-Band L-Band UHF VHF Elev Ionosphere 6 m 32 m 280 m 2 km < 20 °
MIT Lincoln Laboratory2001 Space Control Conf. -19RLL 4/3/2001
GRIMS: GPS Real-Time IonosphericMonitoring System
• MIT Lincoln Laboratory built the firstreal-time ionospheric monitoringsystem based on GPS (1991).– Purpose: Part of a radar calibration
system. Operational systems online atFPS-85, ALTAIR, and Millstone satellitetracking radars.
TEC as Function of Azimuth and Elevationaround Millstone Hill Radar, MA
MIT Lincoln Laboratory2001 Space Control Conf. -20RLL 4/3/2001
Scintillation
Scintillation cancause additional
errors.
For GPS, theprimary issue isloss of lock. For
radars, the primaryissue is
degradation ofcoherent
integrationcapabilities.
MIT Lincoln Laboratory2001 Space Control Conf. -21RLL 4/3/2001
G M T S E C O N D S
RC
S (d
Bsm
)
- 5 0
- 4 0
- 3 0
- 2 0
- 1 0
0
1 0
6 4 8 0 0 6 4 9 0 0 6 5 0 0 0 6 5 1 0 0 6 5 2 0 0 6 5 3 0 0 6 5 4 0 0
Negligible scintillation
Time of day (sec GMT)65100 65200 65300 65400
100
-10-20-30-40-50
RC
S (d
Bsm
)
44200 44300 44400 44500 44600Time of day (sec GMT)
44000 44100
Moderate scintillation
ALTAIR VHF Observations on CAL Sphere 2826:Normal Conditions versus Severe Scintillation
0 5-5 10
0 5-5Frequency (Hz)
Frequency (Hz)-10
-10
Pow
er s
pect
ral
dens
ity (L
og)
Pow
er s
pect
ral
dens
ity (l
og)
Spectrum in Severe Scintillation
100
-10-20-30-40-50
RC
S (d
Bsm
)
10 64900
Cablewrap
65500
Intense scintillation
10 d
B
Normal Spectrum
G M T S E C O N D S
RC
S (d
Bsm
)
- 5 0
- 4 0
- 3 0
- 2 0
- 1 0
0
1 0
6 4 8 0 0 6 4 9 0 0 6 5 0 0 0 6 5 1 0 0 6 5 2 0 0 6 5 3 0 0 6 5 4 0 0
Negligible scintillation
Time of day (sec GMT)65100 65200 65300 65400
100
-10-20-30-40-50
RC
S (d
Bsm
)
44200 44300 44400 44500 44600Time of day (sec GMT)
44000 44100
Moderate scintillation
0 5-5 10
0 5-5Frequency (Hz)
Frequency (Hz)-10
-10
Pow
er s
pect
ral
dens
ity (L
og)
Pow
er s
pect
ral
dens
ity (l
og)
Spectrum in Severe Scintillation
100
-10-20-30-40-50
RC
S (d
Bsm
)
10 64900
Cablewrap
65500
Intense scintillation
10 d
B
Normal Spectrum
G M T S E C O N D S
RC
S (d
Bsm
)
- 5 0
- 4 0
- 3 0
- 2 0
- 1 0
0
1 0
6 4 8 0 0 6 4 9 0 0 6 5 0 0 0 6 5 1 0 0 6 5 2 0 0 6 5 3 0 0 6 5 4 0 0
Negligible scintillation
Time of day (sec GMT)65100 65200 65300 65400
100
-10-20-30-40-50
RC
S (d
Bsm
)
44200 44300 44400 44500 44600Time of day (sec GMT)
44000 44100
Moderate scintillation
0 5-5 10
0 5-5Frequency (Hz)
Frequency (Hz)-10
-10
Pow
er s
pect
ral
dens
ity (L
og)
Pow
er s
pect
ral
dens
ity (l
og)
ALTAIR VHF TracksCalibration Sphere 2826
.5 m diameter, 850 km circular orbit
Spectrum in Severe Scintillation
100
-10-20-30-40-50
RC
S (d
Bsm
)
10 64900
Cablewrap
65500
Intense scintillation
10 d
B
Normal Spectrum
G M T S E C O N D S
RC
S (d
Bsm
)
- 5 0
- 4 0
- 3 0
- 2 0
- 1 0
0
1 0
6 4 8 0 0 6 4 9 0 0 6 5 0 0 0 6 5 1 0 0 6 5 2 0 0 6 5 3 0 0 6 5 4 0 0
Negligible scintillation
Time of day (sec GMT)65100 65200 65300 65400
100
-10-20-30-40-50
RC
S (d
Bsm
)
44200 44300 44400 44500 44600Time of day (sec GMT)
44000 44100
Moderate scintillation
0 5-5 10
0 5-5Frequency (Hz)
Frequency (Hz)-10
-10
Pow
er s
pect
ral
dens
ity (L
og)
Pow
er s
pect
ral
dens
ity (l
og)
Spectrum in Severe Scintillation
100
-10-20-30-40-50
RC
S (d
Bsm
)
10 64900
Cablewrap
65500
Intense scintillation
10 d
B
Normal Spectrum
MIT Lincoln Laboratory2001 Space Control Conf. -22RLL 4/3/2001
Solar Flare of 14 July 2000
Biggest Solar Storm in Nine Years Strikes Earth
MIT Lincoln Laboratory2001 Space Control Conf. -22RLL 4/3/2001
Solar Flare of 14 July 2000
Biggest Solar Storm in Nine Years Strikes Earth
Est. Planetary Kp (3 Hr.) Begin: 2000 Jul 14 0000 UT es
NOAA/SEC Boulder, CO USA
MIT Lincoln Laboratory2001 Space Control Conf. -23RLL 4/3/2001
0
20
40
60
80
100
120
140
160
180
0 5 10 15 20 25 30UTC Time (Hours) starting at day 197
TEC
Uni
ts
POR4WES2NRC1MHR3EGL2
TEC Disturbances on 15 July 2000
MIT Lincoln Laboratory2001 Space Control Conf. -23RLL 4/3/2001
0
20
40
60
80
100
120
140
160
180
0 5 10 15 20 25 30UTC Time (Hours) starting at day 197
TEC
Uni
ts
POR4WES2NRC1MHR3EGL2
TEC Disturbances on 15 July 2000
MIT Lincoln Laboratory2001 Space Control Conf. -24RLL 4/3/2001
GPS Loss of Lock at Ottawa andMillstone Hill
0
5
1 0
1 5
2 0
2 5
3 0
3 5
4 0
4 5
1 5 . 5 1 5 . 7 5 1 6 1 6 . 2 5 1 6 . 5D a y o f M o n t h
TEC
uni
ts
Loss of Lock onGPS L2 signal
GPS Loss of Lock at Ottawa
Local Westward Ion Velocity at Millstone Hill
Zenith TEC Over Millstone Hill
No.
of S
atel
lites
V W
est (
m/s
)TE
C u
nits
15.5 15.75 16 16.516.25Day of Month
MIT Lincoln Laboratory2001 Space Control Conf. -25RLL 4/3/2001
Range Residuals on Calibration Sphere 7646FPS-85 Florida
-50
50
150
250
350
201.87 201.872 201.874 201.876 201.878 201.88
Ran
ge R
esid
uals
(m)
0
100
200
300
400
197.968 197.97 197.972 197.974 197.976
Day of Year (2000)
Rang
e Re
sidu
als
(m)
Typical Residuals
July 15th storm effects
MIT Lincoln Laboratory2001 Space Control Conf. -26RLL 4/3/2001
Summary
• Space-Based Visible sensor sensitive to proton radiationenvironment (e.g., SAA)
– Transient effects (solar proton events) can degrade SBV performance
– Long-term changes in the radiation environment may also affectperformance of space-based sensors
• Ground-based radar measurements: ionosphere introduceserrors
– Range Delay and Angle Errors
– Scintillation
• In general, geomagnetic storms make these errors larger andharder to model
• Understanding of space environment facilitates future space-based and ground-based systems