space weather: why it matters and what we can do about it 16 may 2011
DESCRIPTION
C/NOFS. DMSP. Space Weather: Why it matters and what we can do about it 16 May 2011. CRESS. William J. Burke Air Force Research Laboratory Space Vehicles Directorate Boston College Institute for Scientific Research. U.S. Space Program: Strategic Perspective. MSX. - PowerPoint PPT PresentationTRANSCRIPT
Space Weather: Why it matters and what we can do about it
16 May 2011
William J. Burke
Air Force Research Laboratory Space Vehicles Directorate
Boston College Institute for Scientific Research
DMSPC/NOFS
CRESS
2
U.S. Space Program: Strategic Perspective
Administration Policy or Treaty
• Eisenhower 1955 - Open Skies Proposal
• Kennedy 1963 - Nuclear Weapons Test Ban Treaty
• Johnson 1967 - Principles Governing the Exploration and Use of Outer Space
• Nixon 1972 - International Liability for Damage Caused by Space Objects
• Carter 1979 - Prohibition of Military or Other Hostile Use of Environment Modification Techniques
MSX
3
Space Weather Overview
Near-Earth space is the very hostile environment in which we mustconduct very expensive operations for both national security and advancing scientific understanding about our star and the cosmos.
• Comparison with severe terrestrial weather
• Solar sources of space climatology and weather:
– Extreme ultraviolet radiation maintenance of the ionosphere and thermosphere
– Solar wind and interplanetary magnetic field coupling to Earth’s magnetic field
– Energy storage and transport in the magnetosphere
depletions that map to image depletions/enhancements on the bottomside.
– Magnetic storms: a big electric circuit in the sky
• Some space weather impacts from an Air Force perspective
– Lost in space Satellite and debris tracking
– Communications and navigation ionospheric irregularities
– Radiation damage to spacecraft components taking control
4
Comparative Meteorologies
• New England Weather
– Hurricane of ‘38
– Blizzard of ‘78
• Comparative Sizes
– Thermonuclear device ~ 1015 Joules = 1 MT
– Solar luminosity 4 x 1026 Joules/s = 400 Billion MT/s
– Solar flux on Earth ~1017 Joules/s = 100 MT/s
– Stormtime power into > 1012 Joules/s = 1 MT/hrupper atmosphere
Solar/space disturbances are just too big to ignore.
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The Visible and Invisible Sun
Simultaneous views contrasting quiescent photosphere at visible wavelengths with turbulent X-ray emissions of the corona.
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Coronal Mass Ejection (CME) observed by LASCO white light coronagraph on SOHO
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SPACE WEATHER EFFECTS:
Solar Wind- Magnetosphere Interactions
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Solar wind:• Speeds: 300 – 1,000 km/s• Densities: 2 – 100 cm-3
• IMF: 2 - 80 nT• Imposed stormtime potentials on magnetosphere up to 250 kV• Imposed field-aligned currents to ionosphere up to several 10s of MA• Power: several tera (1012) Watts
88
Satellite Drag Environment
Air Force Space Command tracks about 12,800 objects.
About 10% are active payloads.
Others are inactive payloads, rocket bodies and associated debris.
Over 4000 objects are at altitudes below 700 km where aerodynamic drag is significant.
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Two Major Space Weather Effects
Degradation/loss of signals
C/NOFS
Satellite/debris drag
CHAMP
Actual Position
Predicted PositionProblems
Responses
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Magnetic Storm Effects
Creation of a new radiation belt by a shock wave during the March 1991 magnetic storm
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Never has so much depended on something so small!
Current US policy calls for use of commercial off-the-shelf micro-electronics on all future spacecraft.
Tradeoff: Cost versus reliability/survivability
1/4
Chip in the eye of a needle
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Space Situation Awareness
Compact Environmental Anomaly Sensor (CEASE)
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Mitigation of Space Hazards
• Use available monitors to predict magnetic storms
• Automate situation awareness for satellites
– Radiation environment monitors - CEASE
– Spacecraft discharging
• Control radiation belt fluxes
– Number of energetic particles not large
– Give nature a helping hand: ELF/VLF antennas in space
14
High Altitude Nuclear Detonation (HAND)Impacts Multiple Systems
• High-altitude nuclear tests of 1958 and 1962 demonstrated wide-area affects. Significant military system impacts
– Radars: Blackout, absorption, noise, clutter, scintillation
– Communications: Blackout, scintillation fading, noise, connectivity
– Optical Sensors: IR, Visible, UV backgrounds, clutter; radio noise
– Satellites: Trapped radiation; radiation damage to electronics
– Electronics & Power: Electromagnetic pulse; electrical systems damage
STARFISH1.4 MT at 400 km
ORANGE 3.8 MT at 43 km
KINGFISH__ MT at __ km
TEAK3.8 MT at 76.8 km
CHECKMATE__ MT at __ km
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HAND Belt50 kT, 31.3 deg, 75.2 deg, 200km
Nuclear vs Natural Environment (~800km Polar Orbit)
1E+01E+11E+21E+31E+41E+51E+6
1 14 30 365Days
Do
se
(R
ad
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i)
NuclearNatural
High Altitude Nuclear Detonation produces huge increase in radiation for satellites – all LEO spacecraft fail within months – Devastating to our military intelligence, national security and world economy!
High Altitude Nuclear DetonationWhat is the problem?
900
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25
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0 10 20 30 40 50 60 70 80
Blu
e L
EO
Sat
elli
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Ali
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nat
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al, m
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and
com
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30 KT, 500 km
10 KT, 300 km20 KT150 km
500 KT 125 km
Days into Campaign
Blue satellite attrition curvesSource: AFRL/VSES
16
Physics of Pitch-Angle Scattering
ELF/VLF Waves Control Particle Lifetimes
L shell = distance/RE
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Key scientific questions:Wave-particle scattering: Are interactions diffusive or coherent? Can tailored wave forms improve efficiency?
Global wave propagation and amplification: Where does wave power go in the far field? Can waves be amplified through plasma processes?
ELF-VLF wave injection efficiency: Can ground-based antennas radiate VLF efficiently through the ionosphere? Can space-based antennas radiate VLF into the far-field at high power levels?
VLF wave generation
Wave propagation
Wave-particle interaction
Ionosphere
Outer-zone electrons
HAND belt electrons
Radiation Belt Remediation (RBR)Radiation Belt Remediation (RBR)
Mission: Understand the physical methods of remediating an enhanced radiation belt as a result of a HAND using VLFPayoff: LEO space asset lifetimes are extended and the reverts the radiation environment to acceptable levels for spacecraft replenishment following attack
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Thin Film Photovoltaics• 10X more Available Power• Enables 50 – 100kW range• High radiation tolerance and
thermal annealing
Radiation-Belt Remediation• 50-m Boom & Truss used for VLF
transmit & receive antenna• Actively counter effects of Solar Storms
or HAND
System ID & Adaptive Control• 60X decrease in structural dynamics• ACS autonomously corrects for structure changes due to radiation, failure, etc• Enabling technology for future lightweight structures
25-m
16-m
5-m
25-m
6000-km x 12000-km MEO orbit
Cygnus (DSX)Functional Baseline
Goal: Remove Power, Aperture, and MEO as constraints to DoD Space Capability
Transformational Deployed Structures• 25-m Boom• 25-m Truss• Roll-out Solar Array structure
Space Weather Sensor Array• Data for models in critical orbit• Validate Radiation-Belt Remediation• Correlate Structures and PV radiation
effects
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CLUSTER observations of HAARP VLF signals – 26 Jan 03
3.125 kHz
3.375 kHz
“First light” from conjugate point VLF buoy
RBR Phase 1 Results:VLF from HAARPRBR Phase 1 Results:VLF from HAARP
HAARP experiments are crucial to understand VLF injection/amplification in the magnetosphere– a key enabler for an operational mitigation system
HAARP experiments are crucial to understand VLF injection/amplification in the magnetosphere– a key enabler for an operational mitigation system
Initial 2-hop >10 dB amplification – steady amplitude for next several hops!
HAARP ionospheric heating facility
2-hop 4-hop 8-hop6-hop 10-hop
One experiment complete before HAARP down for antenna-build
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Some Conclusions
• U.S. enjoys vast superiority in space operations.
• Sensors and electronics on space-based platforms are
vulnerable to solar-induced hazards.
• Our experience in space is still quite limited.
– Can satellites survive the solar storm of the century?
– Warnings reduce RISK.
– Space weather forecasting is a necessity.
– Engineers must know why anomalies occur.
– Radiation control gives nature a helping hand.
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Backup Pictures
AF Geospace
Radar Clutter Map
SATCOM Outage Map
DMSP Models
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Backup Pictures
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Hazards to Space Systems
Space Particle Hazards
• Radiation degradation and electronics upsets• Surface and internal
charging / discharging
Ionospheric Hazards
• Comm/Nav link degradation and outage• Surveillance clutter• Satellite Drag
Adversary-Induced Hazards
• High energy particles• RF Waves
Direct Solar Hazards
• Radio, optical and X-ray interference• Solar energetic particle
degradation and clutter