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Space Science Research in Antarctica.
Dr Pierre Cilliers
SANSA Space Science Directorate
www.sansa.org.za
2016-11-03 SA Norway Space Weather week
meeting, Kirstenbosch, Cape Town
The Earth’s space environment
Schematic diagram of the sun, solar wind, and Earth’s magnetosphere.
This is the environment in which space weather is generated.
Near Earth Space
SOHO and ACE satellites
DGI Space Weather
Course 1-3 Apr 2008
4
Sunspots & Coronal Mass Ejections (CME’s)
CMEs ejected from sunspots are 1,000,000,000 tonnes of
charged particles moving at supersonic speeds of up to 2000 km/s
5
Solar cycle based on number of sunspotsSunspots are concentrations of magnetic flux associated with flares on the sun.
They appear dark because they are cooler than the surrounding. The number of
sunspots increase and decrease over an 11 year cycle. The peak of the next
solar cycle, cycle 24, is currently predicted to be at about 2011..
• Disturbances in the solar wind arrive at the Earth within 1-2
days after a violent event on the Sun.
• The largest, non-recurrent geomagnetic storms are
produced by coronal mass ejections.
• Recurrent geomagnetic storms are caused by fast solar
wind streams emanating from coronal holes.
• Space Weather is always worse at the poles due to the
convergence of the geomagnetic field lines.
Solar wind & geomagnetic storms
• The magnetic field lines converge at the poles
Geomagnetism
• Charged particles map space down to the high latitudes
Particle movement
Aurora formation
• Aurora lines map the direction of the magnetic field lines
when precipitating solar wind particles cause auroras in
high latitude regions.
Aurora “lines”
Auroral Australis at SANAE
24 Sept 2006. Photo credit: Fritz Grobbelaar
Auroral Borealis seen from Tromsø,
Norway.Photo credit: https://norway.nordicvisitor.com/
• Convergence of magnetic field lines that carry information
about the solar wind from near-space to the Earth
• Low Electromagnetic Pollution
• Land specifically reserved for Science – Antarctic treaty
• Proximity to the South Atlantic Anomaly
Why Space Science in Antarctica?
During the first International
Polar year, 1882, simultaneous
observations of the aurora and
the magnetic field of the Earth at
both poles, contributed to the
recognition by the Norwegian
Scientist, Christian Birkeland,
that there must be charged
particles carrying electric
currents in the ionized upper
atmosphere of the Earth, which
link the Aurora to fluctuations in
the Earth’s magnetic field.
Photo: Fritz GrobbelaarAurora at SANAE 2005
• IPY1 (1882-83)
• IPY2 (1932-33)
• IPY3 (1957-58)
• IPY4 (2007-09)
First magnetic observatory in South Africa established on UCT
campus – moved to Hermanus in 1941.
2nd International Polar Year (1932-33)
The first buildings of
the Hermanus
Magnetic
Observatory on the
outskirts of
Hermanus in 1941
Buildings on University of
Cape Town (UCT)
campus which housed
the fist magnetic
observatory instruments
in 1932.
LaCour Magnetometer in Norwegian Research Station under the Antarctic ice
3nd International Polar Year & IGY (1957-58)
Aurora as
seen from
the South
African
Antarctic
Research
base
SANAE-IV
17
ICSU INTERNATIONAL POLAR YEAR 2007/2008 PROJECT:
Polar Space Weather studies during IPY/IHY
Better understanding of the Space
Weather and Geomagnetic Storm
mechanisms will allow more effective
prediction of storm intensity and better
mitigation actions to be taken.
IPY4 (Participants in ICESTAR project 63)
SANAE-IV
SANAE IV on Vesleskarvet
Photo: Carol Jacobs
South African Antarctic Research Station SANAE – IV
Midnight 31 December 2006
Photo: Anton Feun
SOUTH ATLANTIC MAGNETIC ANOMALY Main Field Total Intensity F at ground level from IGRF10
Total magnetic field reduced by 10% in 20 years
Total magnetic field reduced by 20% in 60 years
Flux of energetic electrons observed by a polar orbiting satellite 800 km
above the Earth’s surface during a large magnetic storm.
Space Science & other Physical Science
Instrumentation at SANAE-IV
•HF radar
•Aurora cameras
•Radio Opacity meters
•Magnetometers
•VLF-receiver
•GPS receiver for
ionospheric tomography
•GPS Scintillation receiver
•Neutron Monitors
•Seismometer
•Meteorology
South African Space Science projects currently
supported by SANAP grants
PI Surname Institution Short Title
Cilliers SANSA Polar Space Weather Studies
Combrinck HartRAO
SANAP Space Geodesy
Marion/Gough/Antarctica
Kosch SANSA SANAE HF Radar
Kruger NWU Cosmic-ray research
Sievers UKZN Observing Dawn in the Cosmos
Space Weather Instruments deployed
during IPY4 (2006-2009)
FGE 3-axis magnetometer (2007)
DI flux
magnetometer on
non-magnetic
theodolite(2006)
GPS Ionospheric
scintillation
monitor (2006)
GPS receiver (< 2006)
Overhauser Total Field
magnetometer (2006)
Astronomy
Meteorology
I-TASC Automatic Weather Station…
Meteorology
HF SuperDARN Radar
SuperDARN radarsCoherent scatter radars 8-20 MHz
Tx peak power = 9.6 kW
Range ~1000-3000 km
15-45 km range resolution
~30s time resolution
16 beams
12 in southern hemisphere
22 in northern hemisphere
Observe plasma flow in the
ionosphere 200-300 km altitude
http://superdarn.org/tiki-index.php
New SuperDARN HF Radar Antenna
Installed at SANAE in 2009-2010
Overlapping fields of view of Antarctic HF Radars
Electron Convection Plot
• During the Austral Summer of 2013/14, the South African
National Space Agency (SANSA) became the second
organization to install the T3 implementation of the all-
digital HF Radar in the SuperDARN network.
• The new radar transceiver system was fully built and tested
at SANSA Space Science in Hermanus, South Africa and it
was funded through grants from the South African National
Research Foundation and SANAP.
• SANAE IV’s strategic location close to the South Atlantic
Anomaly makes the data invaluable for geospace
observations.
SuperDARN Radar
Digital upgrade of the SuperDARN HF
Transceivers 2013
First data from the new digital radar 2014-02-18
XXXII SCAR OPEN SCIENCE CONFERENCE 13-25 July 2012, Portland, USA
Ionospheric total electron
contentand scintillation monitors
Ionospheric effects on GPS
Delay
Ionization perturbs the signal
propagation speed. Error
proportional to total electron
content: tens of metres error
at solar maximum.
Scintillation
Fluctuations in ionization
density causes rapid changes
in the intensity and phase of L-
band radio waves. Decreases
GPS accuracy.
Images: Credit Bath University
43
Distribution of ionospheric scintillation
Photo: Martin Louw
Crevasces from the air
Crevasce from closer by
Photo: Helena Kruger
46
Local midday
Quiet day σΦ vs azimuth
Quiet day σΦ vs time
Local midday
Active day σΦ vs azimuth
Active day σΦ vs timeGeomagnetically Quiet day Geomagnetically Disturbed day
DemoGRAPE SCAR project at SANAE-IV
Demo GRAPE Hardware
First recording of scintillations using data from the Galileo GNSS system.
First observations of an ionospheric storm using the suite of scintillation receivers deployed bythe DemoGRAPE project at SANAE-IV. There is a clear enhancement of phase scintillation (σφ) onboth the L1 and L2E5 frequencies visible on all three GNSS constellations received at SANAE on1 January 2016, a day with a moderate geomagnetic storm.
Neutronmonitors to study cosmic
ray modulation by the ionosphere
SANAE-IV Neutron
Monitors• Since April 1997:
• Part of network of 4 neutron
monitors operated by NWU
• 6NM64, 627,000 counts/hr,
and 4NMD, 32,800 counts/hr.
Neutron Monitors, Unit for Space Physics, NWU
40
50
60
70
80
90
100
110
1950 1960 1970 1980 1990 2000 2010
Year
Co
unt
Ra
tes (
no
rma
lise
d)
Tsumeb
Potchefstroom
Hermanus
Sanae
Cosmic Rays and Sunspots
60
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80
90
100
110
1950 1960 1970 1980 1990 2000 2010
Year
Co
sm
ic R
ay
In
ten
sit
y
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Su
ns
po
t N
um
be
r
Sunspots
Hermanus Neutron Monitor
Cosmic rays
Monitoring cosmic rays is one way to gain a better
understanding of the very complex relationship between
the earth and the rest of the universe.
Although the research of cosmic rays began nearly 100
years ago much is still unknown especially with regard to
their origins and the mechanisms providing the particles
nearly the speed of light. That is why the cosmic ray
research continues to be one of the most fascinating
adventures of modern space science.
Very Low Frequency (VLF)
Radio receivers
VLF waves caused by lightning travel along magnetic fields lines
through the magnetosphere and are detected in the opposite
hemisphere.
Very Low Frequency (VLF)
monitor at SANAE
• Space Physics Research Institute (SPRI) at UKZN jointlyoperates and maintains a large array of installations atSANAE
• Very Low Frequency (VLF) systems: One broadband VLFantenna, an automatic whistler detector, a narrowband VLFsystem and a new AWESOME (Atmospheric WeatherElectromagnetic System for Observation Modelling andEducation) VLF receiver, with the ability to monitor bothbroad and narrowband signals.
• Lightning strikes are monitored by the new real-time WorldWide Lightning Detector Network (WWLLN) node,
• and variations in the Earth’s magnetic field with periodsgreater than two seconds are measured by a pulsationmagnetometer.
UKZN
Links with climate changeParticle precipitation from space is
one of the routes by which the Sun
can link to the climate – energetic
electrons and protons can change
atmospheric chemistry.
Particle precipitation
Production of NOx and HOx
Change in dynamics
mesosphere & stratosphere
Destruction of mesospheric
and upper stratospheric O3
“Climate” ??
Thank you for your attention
SANSA – in service of humanity
