Space Weather

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Space Weather

• Steve Schwartz
• Space and Atmospheric Physics
• Imperial College London
• With thanks to
• Rainer Schwenn
• Max Planck Institute
• Lindau, Germany

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The Sun Gives Off More Than Light
And the Earth is More than Rock and Air
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Space Weather
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Solar Seasons
Interplanetary magnetic flux
Owens et al. (Imperial), 2008
Sunspot number
Note that the current minimum is longer and
deeper than previous ones.
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The Sun last week
Could be an add for Clearasil!
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Solar Weather
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Interplanetary Weather
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The Sun as a driver of Space Weather

• Major geomagnetic storms may cause
• bright aurorae, down to low latitudes,
• damage to high voltage lines in arctic regions,
• anomalous corrosion of oil pipelines in arctic
  regions,
• damage to long distance communication cables,
• malfunction of magnetic compasses,
• damage to satellites and satellite systems,
• effects on biological systems.

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Activity in geospace What causes the problems?

• Electromagnetic Radiation Flare X-rays and UV
  affect ionosphere/communications.
• Energetic particles (ions) form shock wave, move
  magnetosphere inside GEO, enhance radiation
  belts, and cause geomagnetic storms substorms.
• Geomagnetic storm disturbed fields current
  systems, surface charging.
• Auroral Substorm current systems and fields
  affect satellites directly.
• Killer Electrons increase at GEO after low level
  magnetic storm, last for weeks.

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Space Weather effects are REAL
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And DANGEROUS
Solar Energetic Particle (SEP) Radiation events
during the era of the Apollo Missions (from
Lockwood and Hapgood, 2007)
Slide courtesy M Lockwood
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Big drivers are Coronal Mass Ejections (CMEs)
Bright outer loop Dark Void Bright inner kernel
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Bastille day event 14 July 2000
Second largest flare of the solar cycle Observed
by TRACE satellite
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B
flare
Bz
GOES-X-rays
SW density
shock
cloud
SW speed
The Bastille 2000 events
Dst-Index
Kp-Index
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The Bastille 2000 events X 5.7 flare
July 14, 1024 Arrival of energetic
particles at 1 AU 1038 Shock at 1 AU
July 15, 1429 Travel time
28 hours Initial CME speed
gt1775 km/s Average travel speed
1520 km/s Shock speed at 1 AU
900 km/s Kp max
9 Dst min -281
nT
Aurora observed in Essen, Germany, on July 16,
2000 at 0100
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Bastille day effect on Earth
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Bastille day effects on spacecraft

• ASCA (Advanced Satellite for Cosmology and
  Astrophysics) lost attitude fix resulting in
  solar array misalignment and power loss,
  satellite probably lost
• GOES-8 -10 SEM Electron sensor problems,
  power panels
• ACE (Advanced Composition Explorer) Temporary
  SW and other sensor problems
• WIND Permanent (25) loss of primary
  transmitter power Temporary loss of Sun and
  star sensors
• SOHO (also YOHKOH TRACE) High energy protons
  obscure solar imagery
• GEO and LEO Satellites S/C orientation problems
  during MPE
• GEO Satellites lost 0.1 amp output from solar
  arrays

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What makes geospace so vulnerable? Sign of Bz
Reconnected Magnetic Field
Bow Shock
Cusp
Solar Wind
Sub-solar Reconnection
Magnetopause

• Magnetic reconnection at the frontside of the
  magnetosphere occurs, when the interplanetary Bz
  turns south, i.e. antiparallel to the Earths
  intrinsic field.
• Charged particles can now penetrate from outer
  space way down into the polar ionosphere.

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The Cluster Mission

• Study Key Boundaries
• Bow Shock
• Magnetopause
• Cusp
• Geomagnetic Tail
• Study Key Physics
• Shock Waves
• Particle Acceleration
• Magnetic Reconnection
• Magnetic Storms and substorms
• Separate Space and Time

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Cluster 1 History
Ariane 501 June 1996
40 seconds later
Next day
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What went wrong?

• Primary guidance computer arithmetic overflowed
  (V faster IV) after 36 secs (of 40 secs needed)
• Secondary identical no help!
• Error msgs -gt guidance system
• Thinks OFF Course!
• Rest is History
• Code only needed for IV ?

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The Good News

• Two Cluster spacecraft aboard a Soyuz-Fregat
  Launcher
• Baikanour
• July 2000

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The Present THEMIS tracks the storm sequence
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The present STEREO sees in 3D what will hit us!
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The Future KuaFu a Sino-Canadian-European
Space Weather Mission
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The Future Understanding the physics with
Cross-Scale

• Universal processes
• Shocks
• Reconnection
• Turbulence
• Responsible for
• Energising particles
• Controlling flows
• Redistributing momentum energy
• In
• Astrophysics
• Laboratories (fusion)
• Space (where can sample directly)
• Involving COUPLING of 3D scales
• Joint European-Japanese Canada, USA, (gt2017)

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The End

• Space Weather is Real
• Space Weather has
• Technical implications, especially in modern
  satellite era
• Financial implications (measured in billions of
  pounds)
• Biological consequences hazards to pilots,
  astronauts,
• (only planets with a magnetic field can retain
  water and volatiles, and protect life)
• Interesting and universal phenomena behind it