Transcript BRIEFING TITLE - ALL CAPS 30 Jan 01

Space Weather: Why it matters and what we
can do about it
CRESS
16 May 2011
William J. Burke
Air Force Research Laboratory Space Vehicles Directorate
Boston College Institute for Scientific Research
C/NOFS
DMSP
U.S. Space Program:
Strategic Perspective
MSX
Administration
Policy or Treaty
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Eisenhower
1955 - Open Skies Proposal
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Kennedy
1963 - Nuclear Weapons Test Ban Treaty
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Johnson
1967 - Principles Governing the Exploration and
Use of Outer Space
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Nixon
1972 - International Liability for Damage
Caused by Space Objects
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Carter
1979 - Prohibition of Military or Other Hostile
Use of Environment Modification Techniques
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Space Weather
Overview
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Comparison with severe terrestrial weather
Solar sources of space climatology and weather:
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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
Google
Some space weather impacts from an Air Force perspective
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Lost in space  Satellite and debris tracking
Communications and navigation  ionospheric irregularities
Radiation damage to spacecraft components  taking control
Near-Earth space is the very hostile environment in which we must
conduct very expensive operations for both national security and
advancing scientific understanding about our star and the cosmos.
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Comparative Meteorologies
• New England Weather
– Hurricane of ‘38
– Blizzard of ‘78
• Comparative Sizes
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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
upper atmosphere
> 1012 Joules/s = 1 MT/hr
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
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
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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
Satellite/debris drag
Problems
Predicted Position
Actual Position
CHAMP
Responses
C/NOFS
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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!
Chip in the eye of a needle
1/4 
Current US policy calls for use of
commercial off-the-shelf microelectronics on all future spacecraft.
Tradeoff: Cost versus reliability/survivability
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Space Situation Awareness
Compact Environmental Anomaly Sensor (CEASE)
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Mitigation of Space Hazards
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Use available monitors to predict magnetic storms
Automate situation awareness for satellites
– Radiation environment monitors - CEASE
– Spacecraft discharging
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Control radiation belt fluxes
– Number of energetic particles not large
– Give nature a helping hand:
ELF/VLF
antennas in space
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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:
– Communications:
– Optical Sensors:
– Satellites:
– Electronics & Power:
ORANGE
3.8 MT at 43 km
TEAK
3.8 MT at 76.8 km
Blackout, absorption, noise, clutter, scintillation
Blackout, scintillation fading, noise, connectivity
IR, Visible, UV backgrounds, clutter; radio noise
Trapped radiation; radiation damage to electronics
Electromagnetic pulse; electrical systems damage
KINGFISH
CHECKMATE
STARFISH
__ MT at __ km
__ MT at __ km
1.4 MT at 400 km
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High Altitude Nuclear Detonation
HAND Belt
50 kT, 31.3 deg, 75.2 deg, 200km
Dose (Rads Si)
Nuclear vs Natural Environment (~800km Polar Orbit)
1E+6
1E+5
1E+4
1E+3
1E+2
1E+1
1E+0
Blue LEO Satellites Alive
Includes national, military and commercial
What is the problem?
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35
30
1
14
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30 KT, 500 km
25
20
500 KT
125 km
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10 KT, 300 km
20 KT
150 km
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5
0
0
Nuclear
Natural
Blue satellite attrition curves
Source: AFRL/VSES
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50
60
70
80
90
Days into Campaign
365
Days
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!
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Physics of Pitch-Angle Scattering
ELF/VLF Waves Control Particle Lifetimes
L shell = distance/RE
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Radiation Belt Remediation (RBR)
Ionosphere
VLF wave
generation
Wave-particle
interaction
Wave propagation
HAND belt electrons
Outer-zone
electrons
Mission: Understand the physical methods of
remediating an enhanced radiation belt as a
result of a HAND using VLF
Payoff: LEO space asset lifetimes are
extended and the reverts the radiation
environment to acceptable levels for
spacecraft replenishment following attack
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?
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Cygnus (DSX)
Functional Baseline
6000-km x 12000-km
MEO orbit
Space Weather Sensor Array
• Data for models in critical orbit
• Validate Radiation-Belt Remediation
• Correlate Structures and PV radiation
effects
Radiation-Belt Remediation
• 50-m Boom & Truss used for VLF
transmit & receive antenna
• Actively counter effects of Solar Storms
or HAND
25-m
Thin Film Photovoltaics
Transformational
Deployed Structures
• 25-m Boom
• 25-m Truss
• Roll-out Solar Array structure
25-m
• 10X more Available Power
• Enables 50 – 100kW range
• High radiation tolerance and
thermal annealing
16-m
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
5-m
Goal: Remove Power, Aperture, and MEO as constraints to DoD Space Capability
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RBR Phase 1 Results:
VLF from HAARP
3.375 kHz
3.125 kHz
CLUSTER observations of HAARP
VLF signals – 26 Jan 03
HAARP ionospheric heating facility
One experiment complete before HAARP down for
antenna-build
2-hop
4-hop
6-hop
8-hop
10-hop
“First light” from conjugate point VLF buoy
Initial 2-hop >10 dB amplification – steady amplitude for next several hops!
HAARP experiments are crucial to understand VLF injection/amplification in the
magnetosphere– a key enabler for an operational mitigation system
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Some Conclusions
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U.S. enjoys vast superiority in space operations.
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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
Radar Clutter Map
SATCOM Outage Map
AF Geospace
DMSP Models
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Backup Pictures
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Hazards to Space Systems
Direct Solar Hazards
• Radio, optical and X-ray
interference
• Solar energetic particle
degradation and clutter
Ionospheric Hazards
• Comm/Nav link
degradation and outage
• Surveillance clutter
• Satellite Drag
Space Particle Hazards
Adversary-Induced Hazards
• High energy particles
• RF Waves
• Radiation degradation and
electronics upsets
• Surface and internal
charging / discharging
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