Stanford VLF Remote Sensingsolar-center.stanford.edu/SID/AWESOME/Goddard.pdf · Science, Engineering, Educational outreach ... Umran Inan Morris Cohen ... Whistler waves LEP Events,

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)

4

The Ionosphere

Source: HAARP

5

The Magnetosphere

Source: NASA, Rice University

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

8

VLF Transmitters

Source: Great Circle Mapper, Karl Swartz

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

11

Cosmic Gamma Rays

12

Chorus Emissions

13

Lightning Detection

EW

NSIncident wave S

Φ

14

Whistlers in the Magnetosphere

15

Whistler Wave – an Example

Sferics

Whistler

Triggered

emissions

Palmer Station, Antarctica 2 March 1992 0839:06 UT

16

Lightning Induced Electron Precipitation (LEP Events)

Source: Bill Peter

17

LEP Events – an Example

Hurricane

Isabel

18

Early Fast Events

Source: Bill Peter

19

Mesospheric Phenomenon

Source: Nikolai Lehtinen

20

Runaway Electrons

Source: Nikolai Lehtinen

21

Sprites and Early/Fast Events

Early fast events are highly correlated with

sprites, indicating connection with ionospheric

heating and runaway electronsSource: Robert Marshall

22

TGFs and Sferics

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

26

SID Detector - Pictures

Pre-Amp DataQPost-Amp

Wire Loop Antenna

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

29

AWESOME Receiver – Pictures

30

AWESOME Receiver – Data

Data taken from Palmer Station, Antarctica

31

More Data, Calibration

Data taken from Homer, Alaska

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/

34

nQ e it ou s s