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SuperSID - a small-version AWESOME for educational
and research use By Deborah Scherrer
Stanford University
Solar Center
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Overview
What is this project?
What can the instrument do, and not do
SuperSID data
Tracking solar phenomena
SuperSID research
Obtaining instruments
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The Project
Built upon previous SID - inexpensive space weather monitoring instruments for high schools
Development funded by NSF – Center for Integrated Space Weather Modeling
Distribution funded by NASA – International Heliophysical Year
Complement to AWESOME research instruments
500 distributed worldwide
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Centralized Data Repository
Hosted at Stanford
Accessible to anyone with internet
Sites ftp data (software provided)
Data freely available to all and valuable to solar & ionospheric researchers
http://sid.stanford.edu/database-browser
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Package includes extensive educational resources
Manual, installation CD, presentations, etc.
Curriculum Guide
Research Guide
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SuperSID Instruments Simple VLF radio receivers that track
same VLF transmissions that AWESOME does
Similar to AWESOME although smaller sampling rate, less sensitive
Relies on computer sound card to handle sampling
Narrowband data only Inexpensive (~$50) Designed to primarily track solar-
induced changes to the ionosphere, but adaptable to other ionospheric phenomena as well
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SuperSID Data SuperSID takes 96000 samples/sec,
calculates the spectrum, extracts the signal strength at interesting frequencies (~5-7 data points), then drops the 96000 samples in the buffer (to save disk space and hard drive, because SuperSIDs run continuously for months).
Once every 5 seconds, SuperSID samples and saves signal strength for each interesting transmitter SuperSID receives VLF signals from
multiple transmitters, as does AWESOME
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Keeping Time
AWESOMEs use GPS for time stamps SuperSIDs use the system clock
However, some high-end audio cards have trigger inputs that could be synchronized with an external clock (GPS)
One could also expand SuperSID capabilities to work with National Instrument boards (needs additional ~$300). This would not be difficult to add.
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SuperSID vs.
AWESOME
AWESOME 's hardware is superior to SuperSID, but is costly
SuperSID is inexpensive and suitable for enhancing an AWESOME network or for use as educational instruments in high schools and universities
SuperSID software taps into several important open sources (e.g. Python, MatPlotLib) for numerical analysis, graphics, and networking – making it inexpensive and extensible for academic environments.
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Site Requirements
SuperSID consists of a preamp, an antenna, plus a computer with sound card
Access to power
PC with 1 gHz CPU, 128 meg RAM, CD reader, MS Windows (W2000 or newer) or Linux operating system
HD (96kHz) sound card desirable but will work in Europe, Asia, Africa with 48 kHz
Simple antenna
Relatively quiet site (but not as quiet as needed for AWESOME)
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0
0.5
1
1.5
2
2.5
3
07:0
0:0
3
07:3
5:3
1
08:1
0:5
9
08:4
6:2
7
09:2
1:5
6
09:5
7:2
4
10:3
2:5
2
11:0
8:2
0
11:4
3:4
8
12:1
9:1
6
12:5
4:4
4
13:3
0:1
2
14:0
5:4
0
14:4
1:0
8
15:1
6:3
6
15:5
2:0
4
16:2
7:3
2
17:0
3:0
0
17:3
8:2
8
18:1
3:5
6
18:4
9:2
4
19:2
4:5
3
20:0
0:2
1
20:3
5:4
9
21:1
1:1
7
21:4
6:4
5
22:2
2:1
3
22:5
7:4
1
23:3
3:0
9
00:0
8:3
7
00:4
4:0
5
01:1
9:3
3
01:5
5:0
1
02:3
0:2
9
03:0
5:5
7
03:4
1:2
5
04:1
6:5
3
04:5
2:2
1
05:2
7:5
0
06:0
3:1
8
06:3
8:4
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Normal 24 Hr. Data (No flares)
Local Noon
Sunrise
Sunset Nighttime
Nighttime
Daytime
Time in UT
Colors and labels added
Data from a single transmitter
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GOES-12 weather satellite – detects X-rays directly from Sun
Data indications of solar flares
Unlike AWESOME, the SuperSIDs usually detect flares as an increase in
signal strength
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Solar Flare Detection
M2.8 class solar flare on 1 June 2007
Note that 2 sites picked up the flare as a decrease, rather than increase, in signal strength. This is due to destructive
interference of the VLF waves.
7 sites picked up this flare
Problem – very little solar activity in last 2 years because of long minimum in solar cycle
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Flares can be
tracked back
to the solar active region that produced
them
#Event Begin Max End Obs Q Type Loc/Frq Particulars Reg#
#-------------------------------------------------------------------------------
1960 + 1727 1736 1744 G12 5 XRA 1-8A C4.5 3.1E-03 0424
1990 + 1930 1946 1954 G12 5 XRA 1-8A C5.9 5.9E-03 0424
2000 + 2112 2134 2140 G12 5 XRA 1-8A C3.8 3.1E-03 0424
2040 + 2341 2354 0002 G12 5 XRA 1-8A M1.3 8.5E-03 0424
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the Farside (backside) of Sun
Active region 0424
…and even tracked back to
Farside data from the MDI instrument on board NASA/ESA’s SOlar & Heliospheric Observatory (SOHO) spacecraft
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How does the Sun affect the
ionosphere & magnetosphere?
Through normal day-
night ionization
Through solar flares
Through the solar wind
Through coronal mass
ejections (CMEs)
The solar cycle affects all
these
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Day- Night Ionization
During the nighttime, when the Sun is down, cosmic rays ionize only the F layer. Hence, at night, VLF waves bounce off the F layer. Produces
good, strong VLF signal.
During the daytime, the Sun ionizes the F and E layers, and creates the D layer. Hence, during the day, VLF waves bounce off the E layer but lose energy penetrating the D layer. The VLF signal is weakened.
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Solar Flares disrupt this normal
pattern
Solar flare consists of X-ray and UV energy
This high energy ionizes the D layer
VLF waves now bounce off D, without losing energy penetrating through the D layer
Produces stronger VLF signal
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Day, night, and flares changing
ionization
Solar Flare (daytime) Day Night
Strong VLF signal Strong VLF signal Weak VLF signal
– energy lost while
transitting D layer
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Solar Flares
Huge flare of 28 October 2003
“Speckles” are high energy
particles hitting the CCD
When magnetic fields associated with Active
Regions erupt through the Sun’s surface, then tangle, disconnect, and reconnect, they can
release solar flares bright in EUV, X-rays, and
particle radiation.
Solar flares affect the
Earth’s ionosphere
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What causes solar flares?
Magnetic field lines poke through the solar surface,
producing sunspots. The field lines tangle and
disconnect, producting Coronal Mass Ejections. When
the field lines reconnect, energy is transferred to the
surface and a flare may appear.
Caveat: according to
current understanding
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Sample Research Projects
Sunrise/sunset phenomena & changes over time, season, latitude, distance from transmitter, site, weather, etc.
Identifying solar flares, tracking back to Sun, perhaps predicting
Antenna design
Unusual events – thunderstorms, meteor showers, CMEs, GRBs, planetary waves, earthquakes
Electrical interference Eclipses
Correlation with local events (e.g. photovoltaic power plant increases associated with flares, local hospital admissions, etc.)
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Thunderstorms
Thunderstorms detected by German
students (with a short distance between the transmitter, DHO, and
school)
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Dawn
Dusk
January 2007
December 2007
Summer solstice
1 June
Nighttime
Solar Flares
Missing data
UT Time
Transmitter maintenance outtages
Planetary waves?
Ionospheric Research
One year of SID data, collected by Don Rice, solar researcher
UT Time (00-24)
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Obtaining Instruments
Distribution through the
Society of Amateur Radio
Astronomers (SARA)
Send email to
Attendees of the ISWI/MAGDAS Summer School can obtain a SuperSID instrument at no cost (only the cost of shpping)
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Thank You
What are your questions?