Space Weather ADT Phase I R

1
Space Weather ADT Phase IRV 2

• Spacecraft Impacts
• Marsha Korose

2
Solar Cycle

• Solar Max 2000
• Severe storms occur 5 times per year at Solar Max
  and average 2 per year over whole solar cycle
• First for numerous new satellites
• Largest number of satellites exposed to severe
  Space Weather

Disruptive Sun
Quiet Sun
3
Sun System Manifestations
SUN
LOW-MEDIUM ENERGY PARTICLES ARRIVAL 2-3
DAYS DURATION DAYS
ELECTROMAGNETIC RADIATION ARRIVAL
IMMEDIATELY DURATION 1-2 HOURS
HIGH ENERGY PARTICLES ARRIVAL 15 MIN TO FEW
HOURS DURATION DAYS
SOLAR EMISSIONS
Solar Activity Flares, corona, structure
Solar Wind
Solar Radio Noise
UV/EUV/ X-rays
Solar/galactic Energfetic particles
MEASURED PHENOMENA
Neutral Atmosphere
Aurora
Radiation Belts
Magnetic Fields/ Disturbances
Ionospheric Properties
4
Operational Impacts Radiation Effects on
Spacecraft

• Deep and Surface Charging
• Caused by Low High Energy Particles
• Discharges cause Upset/Burnout

Solar Activity

• Surface Damage
• Caused by Low Energy Particles, UV X-Rays
• Degradation of Thermal Control Material
• Damage to Solar Cells

Cosmic Radiation

• Single Event Effects (SEE)
• Caused by High Energy Particles
• Memory Changes
• False Sensor Readings
• Processor Latch-up
• Burnout

5
General Satellite System Impacts

• Deep dielectric charging
• Single Events

• Radiation
• Surface charging

• Damage

6
Satellite Problems (Historic)

• Loss/ Lower Life/ Degradation (Some to Total
  Mission Loss)
• Loss of total mission capability
• Degraded solar panels and power systems
• Loss of fuel to change trajectory/attitude
• Numerous particle events (100s) (Some Mission
  Loss)
• Overwhelming number of particle events on one
• subsystem/area
• Leads to redesign of follow-on systems
• Not able to test/simulate/model ahead of time
• Annoyance (Non-mission loss)
• Spurious, single particle events on numerous
  systems
• Usually become routine at ground control
• Impossible to forecast

7
Datasets Status

• NOAA database
• 5034 entries DBIII format (upgraded to ACCESS)
  1970-93
• Each entry is a single event Most inputs are
  bit flips, phantom cmds and memory resets.
  Limited remarks
• Aerospace dataset
• 276 entries Word format 1971-96
• Multiple entries on some. More inputs are
  significant problems
• Remarks and estimate of quality of reports
• NASA dataset
• 300 entries Published pamphlet 1971-94
• Multiple entries on a few. About 1/2 inputs are
  significant problems
• DoDOSA database
• 215 entries ACCESS format 1973-97
• Multiple entries on a few. More than 1/2 are
  significant problems
• Includes ground-based events Compiled for SWx
  study

8
Satellite Impacts Caused by Space Weather

• Total Mission Loss
• 13 satellites (DoD, NASA, commercial) in last 16
  years - 8 were first of a series
• Mission Degradation
• Chronic SWx degradations required redesign of
  subsystem on 12 systems in last 20 years
• New technology or changes in design more
  susceptible to anomalies
• Solar panels or power supplies problems in 21
  satellites in past 10 years
• Subsystem or component limiting mission capability

9
Satellite Mission Failures(Total Mission
Loss)

• Conclusions
• Charging is more dangerous than memory changes
• Silver bullets happen
• Have lost an average 1 sat/ 2 years
• Losses have spanned the years somewhat evenly

• First blocks more susceptible
• Not connected to solar cycle
• Debris2/17, SWx13/17 2
• (J) jury still out on these

NAME DATE REASON MISSION 1stBlk DSCS-II
(9431) 6/2/73 ESD Comm KOSMOS-1275 7/24/81 Debris
Imagery GOES-4 11/25/82 ESD Weather DSP-7 01/24
/85 ESD DoD Arabsat 1-A 6/1/86 ESD Comm TELECOM
1B 1/15/88 ESD Comm FENGYUN-1 10/15/88 ESD Weath
er (China) SUPERBIRD-1 12/90 SEU Comm
(Japan) MARECS-1/A 3/25/91 ESD Comm HIPPARCOS 8/
15/93 RAD Science OLYMPUS 8/30/93
RAD Comm SEDS-2 3/14/94 Debris NASA
Research MSTI-2 9/5/94 Debris/ESD DoD
Exp ETS-6 1/12/96 RAD Comm (Japan) IRON
9906 1997 SEU DoD TELSTAR 401 (J) 1/24/97 ESD Comm
INDIASAT (J) 10/1/97 ESD Comm
10
Solar Panel and Power Impacts(Some Mission Loss)
13 commercial GEOs 10/20/89 Permanent power
panel degradation due to a geomagnetic
storm GOES-5, 6 7 3/24/91 2-3 yrs of use
lost BS3a 3/22/91 1/4 power cells - 1/3
capability lost MARECS-A 3/91 Ceased
operation ETS-6 1/12/96 Radiation reduced
total life to 1 1/2 yrs ANIK E-1 3/26/96 Lost
66 of power TEMPO 4/11/97 Loss of 22 power
- SO FAR MIR Current Chronic power shortages
due to damage to solar panels
11
Redesigns(Some Mission Loss)
These systems had extensive SWx problems and
follow-ons required redesign
DMSP F2 - 1977 chronic charging on one
component METEOSAT F1 11/77 extensive
charging GPS Blk I- clock failures GPS -
6/13/80 solar array tracking GOES-4 81/82
ungrounded radiator HEO signal degradations -
subassembly redesigned TDRSS-1 4/83 attitude
control system Telecom 1A- 8/84 ungrounded
thermal shielding CLAS - extensive loss of
data/noise SUPERBIRD-1 12/90 - SEU affecting
attitude control led to hardened
microprocessors MARECS-A 3/91 continuous
safeing TEMPO 4/97 New technology - increased
power, use of GaAs, solar panel problems
12
Operational Impacts Radiation Charging Example

• 3 TEMPO Satellites Launched (GEO Comm)
• New Technologies were used
• Higher Voltage Solar Arrays (100V)
• Higher Power - 10-11 kW
• New Material - Gallium Arsenide

First Launch - 5 Mar 97 Charging - 11 Apr
97 Charging - 11 Dec 97 Lost 22 power on 2
birds Cost 225M ea Ins Claim of 20M on 1 sat

• Nine month study identified voltage as the
  problem to be reengineered - 40 engineers working
  the problem since April 97

• Follow-ons must be re-engineered before next
  launch

13
GOES SWx Anomalies(No MissionLoss)
of anomalies
Year
GOES 4 - unusable after 1982 GOES 7 - lost 50
solar cells 3/89
Solar Max
NOAA Database
14
GOES Anomalies(No Mission Loss)

• Data shows that most anomalies
• occur in Mar/Apr or Sep/Oct
• (equinoxes).
• Most occur during the late PM/early AM
• This pattern indicates these satellites are
• susceptible to surface charging of trapped
• radiation on the night side
• Anomalies listed as bit flips, phantom
• commands, etc.

Data 1981-94 From NOAA
15
Amount of Time to Resolve Satellite Impacts

• Time frame of hr-day includes
• anomalies that must wait for
• another pass to resolve, must
• do more than a pre-programmed
• algorithm, or must have per-
• mission or another operator to
• resolve
• Less than hr-day is probably
• no mission loss
• Greater than hr-day is probably
• some mission loss

of r e c o r d s
From Aerospace Data collection
Duration of impacts
16
Observations and Findings

• Energetic particle events can happen throughout
  the solar cycle
• Electro Static Discharges can be catastrophic
• Some SWx radiation environment monitoring is done
  at GEO, very limited monitoring at LEO/MEO/HEO
• SWx impacts are not often understood at the time
  of occurrence
• Only incomplete engineering anomalies databases
  exist
• Design and testing could be improved with more
  detailed knowledge of the SWx environment
• Early satellites in a block tend to have greater
  problems
• Changes in satellite design may cause unexpected
  difficulties due to the radiation environment

17
Hubble Space Telescope (Some Mission Loss)

• Anomaly
• New technology opto-couplers exhibited problems
  in South Atlantic Anomaly
• Impacts
• One instrument had to be turned off for 7 out of
  16 orbits per day
• 50-60 loss of observing time every day

• Cause
• Penetrating high energy electrons in South
  Atlantic Anomaly
• Improper component use

18
GPS Satellite Anomalies(No Mission Loss)

• All GPS errors were soft errors
• (AKA bit flips or low level logic
• errors)
• 7 GPS birds had gt 100 soft errors
• each
• Errors do not show any time correllation
• indicative of more Single Event Upset-type
• events
• Most caused by SEUs, charging and
• radiation
• 954 cases recorded by NOAA/SEC 1984-92.

19
Space Surveillance/ISR/BMD SBIRS-High Satellite
Outage

• TMD Simulation
• Launch point prediction
• 300 km Range TBM

• Failure of a single SBIRS-High satellite can
  significantly
• degrade state vectors and launch and impact
  point predictions
• DSP experience indicates the possibility of
  SBIRS-High Failures
• DSP-7 satellite loss
• DSP 1971-1985, 16 occasions of SEUs leading to
  lost data

Aerospace Analysis
20
DSCS Loss Impacts
900
800
127
700
127
127
116
126
127
600
Pri 1
500
106
106
Pri 2
No. of Requirements
Pri 3
400
583
Other
537
510
510
506
300
492
414
404
200
100
52
45
49
51
42
45
20
18
11
11
8
7
8
0
5 Sats
No EP
No IO
No WA
No Ea
No WP

• Loss of the Western Pacific satellite
  significantly reduces number of requirements
  satisfied
• Requirements based on CJCS MOP37 priority for the
  network

21
Operational Impacts Ionospheric Effects
Ionospheric Turbulence
Undisturbed Ionosphere
Scintillation
Ionosphere

• GPS Loss of Lock
• SATCOM Outages
• Radar Interference

Electron Density
Bend Delay
X
Absorb
Apparent Location
True Location
Ionosphere

• Radar Errors
• Geolocation Errors
• GPS Errors

• HF Radio Outages

22
Operational Impacts Ionospheric Effects Summary
Phenomena
Mission
Impacts
Region/Occurrence
Ionospheric Scintillation

• UHF SatCom Outages
• GPS Loss of Lock
• Radar Interference

• Comm
• PNT
• BMD
• ISR

• Equatorial Geomagnetic Latitudes
• Intermittent Interference from Minutes to Hours
• Greatest variability occurs at Solar Max from
  Sunset to Midnight
• High Geomagnetic Latitudes
• Intermittent Interference from Hours to Days
• Greatest variability occurs at Solar Max during
  Geomagnetic Storms

Ionospheric Electron Density

• HF Comm Loss
• GPS Errors
• Radar Errors
• Geolocation errors

• Comm
• PNT
• BMD
• ISR

• Sunlit Hemisphere
• Significant enhancement to ionosphere during
• major Flares (minutes to hours)
• Averages 5 times/month during Solar Max
• Globally
• Disruptions during major Geomagnetic Storms
• Significant disruptions can occur 40-45 times
• per year during Solar Max (hours to days)

23
Scintillation Vulnerability (backup)
Julian Day 110 Time 18 hr Z Zenith Angle
94 Subsolar Point 11.2N, -90.3E
Latitude (N)
Magnetic Equator
Anomaly Region
-180
-120
-60
0
60
120
180
Longitude (E)
24
Operational Impact Ionospheric Effects Findings

• Ionospheric Scintillation
• Mainly impacts systems operating in UHF and lower
  frequencies
• Ionospheric scintillation problems often
  attributed to unknown
• Documented ionospheric scintillation outages are
  sparse
• UHF SatCom Loss of lock-on by receiver delays
  message traffic causing time-critical mission
  loss
• Growth in UHF SatCom will increase potential
  impact
• GPS Loss of lock-on by receiver to one or more
  satellites
• Radar Increased system noise level interfering
  with acquisition, tracking, and target
  classification (BMD Satellite)

25
Scintillation Effects on UHF SATCOM

• UHF SATCOM (FLTSATCOM, AFSATCOM, UFO,
  LEASAT225-400 MHz)
• Intermittent signal fading and data dropouts due
  to scintillation
• Low latitude - night-time geosynch links minutes
  - hours
• High latitude - auroral zone links hours - days

OCCURRENCE
50
----- Projected Occurrence
40

• UHF SATCOM Outages (Increases up to five-fold
  during Solar Max)
• Frequency of severe signal loss (gt10dB) in
  equatorial region, sunset to midnight is based on
  AFRL data collected at Ascension Island

30
20
10
0
1980
1985
1990
1996
2000
SOLAR MAX
SOLAR MAX
SOLAR MAX
26
OPERATIONAL UHF SATCOM OUTAGE
Historical Example
FLTSATCOM (23o W) 250 to 300 MHz

• 621 Air Mobility Operations Group (AMOG)
• Apr 97 Mission C2 operations
• Transport aircraft inbound to Zaire
• Tactical Air Control Center - Scott AFB
• Forward Operating Base - Ascension Island
• Primary communications UHF SATCOM

TACC
Zaire
Ascension
SATCOM OPERATORS LOG 0010 hrs Began
transmitting several messages. One message took
35 minutes to get through and two others took up
to 1 hour. Normal transmission takes 5 minutes
maximum. 0230 hrs ...I can receive just fine
but cant transmit out. Still trying to send out
original 4 messages. 0247 hrs I got a message
out after trying for 2 hours and 40 minutes...
27
Effective Blue Counterfire Missions
Potential Mission Effects due to UHF
Communication Delays

• Severe scintillation for a Persian Gulf Fire
  Support Scenario
• Severe scintillation cause delays greater than 3
  minutes for 33 of the call for fire messages

JHU/APL Analysis
Communications Delay
28
Quantitative AnalysisFire Support Scenario
UFO ( 36000 km)
F-Region ( 300 km)
Scintillation
UHF Channel Controller
50 nmi ( 93 km)
Forward Element with EMUT
ERGM Ship
29
Fire Support UHF SATCOM Results

• Cases
• Base no scintillation
• M16 low scintillation
• M1 high scintillation
• Delay times in seconds

30
Effective Blue Counterfire Missions
Potential Mission Effects due to Communication
Delays
Kills by Blue Indirect Fire
of Missions
COFM value
(weighted value of kills)
Communications Delay

• Mission effectiveness could be degraded by
  communication delays
• The graphs show impacts due to communication
  delays from a Korean scenario using Tactical Fire
  Simulation Model (TAFSM)

31
Quantitative AnalysisTactical Tomahawk Scenario
32
Tactical Tomahawk Communication Results
Large Message

• Inflight mission updates may have average delays
  of 27 minutes due to high scintillation
• Tactical tomahawk is a potential future mission

33
GPS Impacts
Historical Examples

• 1995 - Loss of lock on 5 dual frequency receivers
  at Millstone radar during major storm (Kp5)
• 1997 - 2 day FAA performance review had an
  anomaly at 4 of 5 stations lasting up to 13 min

• Analysis of measured scintillation (October
  1996), would have caused loss of lock on all but
  two satellites

34
Scintillation Effects on GPS Signals
OCCURRENCE
50
----- Projected Occurrence

• Frequency of severe signal loss (gt10dB) in
  equatorial region, sunset to midnight (based on
  AFRL data collected at Ascension Island)
• GPS navigation vulnerability (Increases up to
  four-fold during Solar Max)

40
30
20
10
0
1980
1985
1990
1996
2000
SOLAR MAX
SOLAR MAX
SOLAR MAX
35
Potential Fading due to Scintillation at L-Band
36
Scintillation Effects on GPS
37
GPS Quantitative Analysis

• Air campaign analysis
• Cases included no scintillation, jamming,
  scintillation with jamming
• Employed PGMs, GPS guided munitions, and
  stand-off weapons
• Mission effectiveness was impacted by severe
  scintillation in a jamming environment
• Scintillation induced state changes in GPS
  receivers can adversely affect precision systems
• Precision approach and landings
• Surveillance and targeting

AFRL Analysis
38
Operational Impact Ionospheric Effects Findings,
cont.

• Ionospheric Electron Density
• Induced errors in geolocation, strategic
  tactical radar and single frequency GPS
• Affects systems operating in UHF and below
• HF signals degraded
• Affects entire sunlit hemisphere
• HF radio will continue to be used
• Proposed (US, allies enemy) space-based radars
  operating at UHF or VHF will be degraded
• Some future ground based radars moving to X-band
  will be less degraded
• Effects can be mitigated with real-time
  measurements of electron density and model
  improvements

39
HF Communications
15
FREQUENCY (MHz)
10
USEABLE FREQUENCY WINDOW
MAXIMUM USEABLE FREQUENCY
5
LOWEST USEABLE FREQUENCY
SHORT-WAVE FADE (SWF)
0
00
24
18
12
06
SOLAR FLARE
TIME
Historical Examples - March 1989 Storm

• HF Radios (hi lat) 2-3 day outages
• HF Radios (low lat) 20 hour outage

• DoD SW radios - 7 day outage
• DoD MARS radio outages up to 24 hours

40
HF Missions
AMC C2 IPS Long Range NAS Recovery Comm AMC
SCOPE COMMAND ALE Army air traffic control ACC
PACER SPEAK FAA oceanic routes Navy HF voice
and email Air to Ground Datalink Army Corps of
Engineers AK/Canada/polar FAA routes FEMA
(w/DoD) DEA (w/DoD) Embassies USA tanks and
APCs Special Operations Forces AWACS ( US and
NATO) NATO HF networks Army Blue water net Army
Nap of the Earth helicopters Federal SHAred
RESources emergency comm USN Intra-fleet Passive
HF geopositioning Relocatable Over-the Horizon
RADAR Secy Army federal net for natural
disasters USA,USAF Central/South American nets
Southern Command net Army/Navy/AF MARS
41
HF Communications
Representative example
Ionospheric Absorption

• U.S. Forces 20 km inland (no line of sight
  communications)
• Fire support request via HF voice to ship at a
  range of 90 km

90 km (50 nmi )
Fire Support Ship
Forward Element with HF Radio
Impact

• HF communications will be out for a half hour to
  several hours due to a Class X flare (5 per month
  _at_ solar max)
• Significant degradation on HF communications are
  expected for Class M flares (75 per month _at_ solar
  max)

JHU/APL Analysis
42
Fire Support HF Communications
Total Loss of NVIS HF Communications due to 10 dB
or greater absorption

• Class X flares will totally wipe out NVIS HF
  communications for a half hour to several hours
  significant degradations also expected for Class
  M flares
• Class M or higher flux levels are expected to
  occur 5 of the time (36 hours/month) during
  sunspot maximum (2000)
• The flares will only affect propagation through
  the daytime ionosphere

43
Polar Network Results
Impact of Routing out of Polar Region during
Grayouts
45
40
35
35
30
30
25
25
Median Message Delivery Time (min)
20
20
15
15
10
10
5
5
0
0
15
80
160
15
80
160
Sunspot Number
Sunspot Number
Normal LQA Routing
Out-of-Polar Routing

• Increased knowledge of space weather allows
  better use of useable frequencies which reduces
  message delay times.
• Rerouting messages out of affected areas can
  reduce message delay times.

44
HF NetworkPersian Gulf Scenario Results
30
Location of Network Nodes McGuire USA Mildenhall
UK Lajes Portugal Ramstein Germany Rhein-Main Ger
many Torrejon Spain Incirlik Turkey Dharhan Saudi
Arabia Jeddah Saudi Arabia
25
20
Median
Message
15
Delivery
Time (min)
10
5
0
15
80
160
Sunspot Number
No Info
LQA
Perfect Info
Cases 1. No space weather information 2. Link
Quality Assessment (LQA) implemented 3. Perfect
space weather information used
45
Surveillance Radar Errors
Missile Detection/Spacetrack Radars and Tactical
Radars (e.g. BMEWS, PAVE PAWS, Cobra Dane)

• VHF/UHF Ionospheric signal absorption/bending/reta
  rdation caused by variations in Ionospheric TEC
  along beam path - variations occur with time of
  day, season, geographic locations, level of solar
  activity

46
Space Surveillance/ISR/BMD Radar Track Accuracy
Ionospheric Electron Density Correction
Meters
Real-time Measurement
Climate Model

• Ionospheric electron density uncertainty is
  dominant limit to track accuracy in Spacetrack
  radars
• Using real-time measurement of the ionosphere can
  yield significant improvements

Lincoln Lab Report
47
TEC Effects on Single Frequency GPS

• L1 signal delays from satellites
• due to TEC
• Expect greatest degradation
• during strong ionospheric
• disturbances potential errors of
• 100m due to ionospheric variability
• Documented examples
• are scarce

48
Operational Impacts Other

• Neutral Density Effects
• Cause Solar heating of Upper Atmosphere
• Impacts Satellite Drag and Diminished Range of
  BMD Interceptors
• Aurora Effects
• Cause Low Energy Particles impacting the Polar
  Atmosphere during geomagnetic storms
• Impacts Signal-to-Noise problems for SBIRS-Low,
  Scintillation for GPS and Radar Clutter for BMD
• Solar RFI Effects
• Cause Solar Event induced Radio Frequency
  Interference
• Impacts Interference of Radio Frequency
  Receivers with the Sun in the field of view

49
Operational Impacts Aurora Effects

• Aurora can occur over both Poles
• Northern Aurora ovals extend from 70 deg N
  latitude to as far South as 40 deg N latitude
  during severe Geomagnetic Storms
• Aurora Impacts
• Signal to noise problems for SBIRS-Low caused by
  IR emissions
• Scintillation for GPS
• Radar clutter for BMD

50
MWIR Radient Intensities

• Radiance from bright aurora can be comparable to
  SBIRS-Low Targets
• Limits lower tangent altitude
• Reduces Battle space available to interceptors
• Especially severe for short range theater missile
  targets

51
Operational Impacts Solar RFI Effects

• SATCOM Radar RFI occurs when
• Sun in Field of View of the Receiver
• Solar radio burst at appropriate Frequency and
  sufficient Intensity

RADAR INTERFERENCE
SATCOM INTERFERENCE
RADIO BURST

• Duration and Frequency of Solar Radio Bursts
• Lasts a few minutes to tens of minutes
• Few events/year during Solar Min
• Hundreds of events/year during Solar Max

52
Historical RFI Events

• Solar events of 6-20 Mar 89 caused RFI
• Severely degraded communications between Falcon
  AFS and Kwajalein on 10 Mar
• Very high noise levels on VHF receiver at Ft
  Huachuca on 8-9 Mar
• Disruption of satellite data reception at Kelly
  AFB on 16 Mar
• Radar systems reported over a dozen interference
  events during the period