stanford vlf remote sensingsolar-center.stanford.edu/sid/awesome/goddard.pdf · science,...
TRANSCRIPT
Stanford VLF Remote SensingScience, Engineering, Educational outreach
Morris CohenAlong with Phil Scherrer, Deborah Scherrer, Umran Inan,
Ray Mitchell, Justin Tan
Space, Telecommunications and Radioscience Laboratory
Stanford UniversityStanford, California 94305
http://www-star.stanford.edu/~vlf/http://sun.stanford.edu
2
Stanford VLF Remote Sensing
� The collaborators
� Ionosphere/magnetosphere overview
� Electromagnetic effects
� SID Receiver
� AWESOME Receiver
� Educational Outreach
3
The Stanford Collaborators
� Phil/Deborah Scherrer
� Ray Mitchell
� Umran Inan
� Morris Cohen
� Justin Tan
� Center for Integrated Space Weather Modeling (CISM)
6
Electromagnetic Effects
� Solar Flare Detection
� Cosmic Gamma Rays
� Chorus Emissions
� Lightning
� Whistler waves
� LEP Events, hurricane studies
� Early/fast Events
� Mesospheric lightning discharges� Sprites, elves, blue jets, TGFs
7
Sudden Ionospheric Disturbance
� Strong solar flares penetrate to lower ionospheric region, cause transient changes
9
SID Event – an Example
2
2.5
3
3.5
4
4.5
5
07:0
0:0
3
07:3
1:2
6
08:0
2:4
8
08:3
4:1
1
09:0
5:3
4
09:3
6:5
6
10:0
8:1
9
10:3
9:4
2
11:1
1:0
5
11:4
2:2
7
12:1
3:5
0
12:4
5:1
3
13:1
6:3
5
13:4
7:5
8
14:1
9:2
1
14:5
0:4
4
15:2
2:0
6
15:5
3:2
9
16:2
4:5
2
16:5
6:1
4
17:2
7:3
7
17:5
9:0
0
18:3
0:2
3
19:0
1:4
5
19:3
3:0
8
20:0
4:3
1
20:3
5:5
3
21:0
7:1
6
21:3
8:3
9
22:1
0:0
1
22:4
1:2
4
23:1
2:4
7
23:4
4:1
0
00:1
5:3
2
00:4
6:5
5
01:1
8:1
8
01:4
9:4
0
02:2
1:0
3
02:5
2:2
6
03:2
3:4
9
03:5
5:1
1
04:2
6:3
4
04:5
7:5
7
05:2
9:1
9
06:0
0:4
2
06:3
2:0
5
Local Nighttime DaytimeSunrise Local Nighttime
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
6
Quiet
Day
Active
Day
NLK
24.8 kHz
Source: Ray Mitchell
10
SID Event – an Example
2
2.5
3
3.5
4
4.5
5
07:0
0:0
3
07:3
1:2
6
08:0
2:4
8
08:3
4:1
1
09:0
5:3
4
09:3
6:5
6
10:0
8:1
9
10:3
9:4
2
11:1
1:0
5
11:4
2:2
7
12:1
3:5
0
12:4
5:1
3
13:1
6:3
5
13:4
7:5
8
14:1
9:2
1
14:5
0:4
4
15:2
2:0
6
15:5
3:2
9
16:2
4:5
2
16:5
6:1
4
17:2
7:3
7
17:5
9:0
0
18:3
0:2
3
19:0
1:4
5
19:3
3:0
8
20:0
4:3
1
20:3
5:5
3
21:0
7:1
6
21:3
8:3
9
22:1
0:0
1
22:4
1:2
4
23:1
2:4
7
23:4
4:1
0
00:1
5:3
2
00:4
6:5
5
01:1
8:1
8
01:4
9:4
0
02:2
1:0
3
02:5
2:2
6
03:2
3:4
9
03:5
5:1
1
04:2
6:3
4
04:5
7:5
7
05:2
9:1
9
06:0
0:4
2
06:3
2:0
5
Local Nighttime DaytimeSunrise Local Nighttime
GOES
Data
Active
Day
NLK
24.8 kHz
15
Whistler Wave – an Example
Sferics
Whistler
Triggered
emissions
Palmer Station, Antarctica 2 March 1992 0839:06 UT
21
Sprites and Early/Fast Events
Early fast events are highly correlated with
sprites, indicating connection with ionospheric
heating and runaway electronsSource: Robert Marshall
23
The Hardware
� SID Detector
� AWESOME Receiver
A tmosphericW eatherE ducationalS ystem forO bservation andM odeling ofE ffects
24
The SID Detector
� Designed by Ray Mitchell
� Low cost, compact, easy to use
� Narrowband amplitude receiver
� 1 sample per 5 seconds
25
The SID Detector – Overview
Pre-Amp
24.8KHzFilter
SignalStrength
DATAQComputer
RS-232
Coax
=
All frequencies
DC voltageLevel
10 bit, Analog to DigitalConversion Sample every
5 Seconds
Source: Ray Mitchell
27
The AWESOME Receiver
� Designed by Morris Cohen, Justin Tan
� Ultra sensitive
� Medium cost (~$2000)
� Narrowband amplitude/phase
� Broadband 100kHz data
� Deployed worldwide
� Auto-calibration
28
AWESOME Receiver – Overview
B-Field Antenna
PreampLong Cable
Line Receiver
Analog to Digital
ComputerGPS
Antenna
32
Educational Outreach
� Center for Integrated Space Weather Modeling (CISM)� Run by Boston University
� Stanford selected for educational outreach
� Distribute SID detectors widely� 3 Beta sites working
� 100 units in production
� 3 foreign sites planned (Tanzania, India, Tibet)
� Distribute selected AWESOME detectors
33
Educational Outreach (con’t)
� Research purpose� data sent to Stanford via internet, DVDs
� Educational purposes� Monitor solar flares/VLF activity� Build antenna, maintain electronics� Participate in research campaigns
� Promote in developing countries through UN?
� http://solar-center.stanford.edu/~SID� http://www-star.stanford.edu/~hail/