1. AAVSO, 99 th Annual Meeting, 2010 Solar Plasma Motion Detection at Radio Frequencies Very Low Frequencies (VLF) Solar Ionosphere Detection (SID) By Rodney Howe MS Remote Sensing, A121

2. AAVSO, 99 th Annual Meeting, 2010 Overview of presentation How VLF detection works A computer analysis for SID detection –Scaling GOES X-ray events to ionosphere disturbance detection with VLF receiver energies –Evaluate detection possibilities and importance ratings Howe A121

3. AAVSO, 99 th Annual Meeting, 2010 VLF Transmitter locations

4. AAVSO, 99 th Annual Meeting, 2010 Transmitting Stations

5. AAVSO, 99 th Annual Meeting, 2010 Transmitting Stations

6. AAVSO, 99 th Annual Meeting, 2010 Transmitting Stations

7. AAVSO, 99 th Annual Meeting, 2010 Transmitting Stations

8. AAVSO, 99 th Annual Meeting, 2010 EM Wave Propagation Copyright © XTR Systems, LLC

9. AAVSO, 99 th Annual Meeting, 2010 Inverse Square Law Copyright © XTR Systems, LLC

10. AAVSO, 99 th Annual Meeting, 2010 EM Interaction With Matter Copyright © XTR Systems, LLC

11. AAVSO, 99 th Annual Meeting, 2010 Propagation and Reflection Copyright © XTR Systems, LLC

12. AAVSO, 99 th Annual Meeting, 2010 Reflection vs. Refraction Copyright © XTR Systems, LLC

13. AAVSO, 99 th Annual Meeting, 2010 Ionosphere Structure Copyright © XTR Systems, LLC

14. AAVSO, 99 th Annual Meeting, 2010 e - Density vs. Altitude Copyright © XTR Systems, LLC

15. AAVSO, 99 th Annual Meeting, 2010 Ionosphere Structure Copyright © XTR Systems, LLC

16. AAVSO, 99 th Annual Meeting, 2010 Incoming solar burst.. HAIL project Stanford University

17. AAVSO, 99 th Annual Meeting, 2010 There are two basic VLF receiver types to validate SID data collection E field antenna and receiver, whip antenna H field Gyrator receiver, loop antenna

18. AAVSO, 99 th Annual Meeting, 2010 Typical Site Configurations Low volume data capture rates –1 second sample rate –<93,000 samples per Day –Intel (386, 486) Hardware or Equivalent ($<200) –Linux OS ($0) or Windows OS –Analog to Digital Meter ($100), or sound card ($0) –Perl, PHP Programming Languages ($0) –C++ Programming Language ($0) –DSL (0.5 Mbps) ($60/month) –Flat-file, Excel Spreadsheet

19. AAVSO, 99 th Annual Meeting, 2010 Example of an E Field Active Antenna Copyright © XTR Systems, LLC

20. AAVSO, 99 th Annual Meeting, 2010 Active Antenna Schematic Copyright © XTR Systems, LLC

21. AAVSO, 99 th Annual Meeting, 2010 Active Antenna Details Copyright © XTR Systems, LLC

22. AAVSO, 99 th Annual Meeting, 2010 Single-channel Receiver Copyright © XTR Systems, LLC

23. AAVSO, 99 th Annual Meeting, 2010 Single-channel Receiver Copyright © XTR Systems, LLC

24. AAVSO, 99 th Annual Meeting, 2010 Logarithmic RF Detector uses the computers sound card Copyright © XTR Systems, LLC

25. AAVSO, 99 th Annual Meeting, 2010 Cutler, Jim Creek, & LaMoure Copyright © XTR Systems, LLC

26. AAVSO, 99 th Annual Meeting, 2010 Gyrator VLF receiver Howe A121

27. AAVSO, 99 th Annual Meeting, 2010 24 turn 1.5 meter loop H Field Antenna Howe A121

28. AAVSO, 99 th Annual Meeting, 2010 Diode Detector Receiver A121

29. AAVSO, 99 th Annual Meeting, 2010 Both receiver types record alike A121

30. AAVSO, 99 th Annual Meeting, 2010 AAVSO Historical data from Doug Welch A104

31. AAVSO, 99 th Annual Meeting, 2010 Some of the monitoring stations that report to AAVSO are: Observer Receiver Location Transmitter and Location Moos Switzerland FTA - St. Assie, France Hill Massachusetts, USA NAA - Cutler, ME, USA Winkler Texas, USA NAA - Cutler, ME, USA Kielkopf Kentucky, USA NAA - Cutler, ME, USA Campbell Alberta, CA NLK - Jim Creek, WA, USA Howe Colorado, USA NML - LaMoure, ND, USA Mc. Williams Minnesota, USA NML - LaMoure, ND, USA Samouce Montana, USA NML - LaMoure, ND, USA Kielkopf Kentucky, USA NPM - Lualualei, HI, USA (2nd receiver) Mandaville Arizona, USA NPM - Lualualei, HI, USA Lewis California, USA NPM - Lualualei, HI, USA Winkler Texas, USA NPM - Lualualei, HI, USA (2nd receiver) The observing method employs the monitoring of distant, powerful VLF radio transmitters; this is a sensitive monitor of the state of the lower ionosphere along the radio propagation path. Due to the sub-burst longitude and latitude and the geographical distribution of LF/VLF beacons and monitoring stations, this burst was not detected by active monitoring stations in Germany, Australia and Canada. However, one monitoring station in Massachusetts, USA (separate from Hill) did not detect the SID while being in a good location to do so.

32. AAVSO, 99 th Annual Meeting, 2010 Solar flare detection requires: SID Start Time, SID Maximum, and the SID End Time (UTC) A121

33. AAVSO, 99 th Annual Meeting, 2010 Importance of Having Friends To validate the solar flares A125 aavso-sid-list@aavso.org

34. AAVSO, 99 th Annual Meeting, 2010 Detection of SID or X-ray transients classified by NOAA- GOES satellites Are these VLF receivers sensitive enough to detect A or B class flares detected from the GOES satellites? Computer analysis may help answer this question. A87

35. AAVSO, 99 th Annual Meeting, 2010 Mike Hill created software to match GOES satellite event data to SID observers A87 – A121

36. AAVSO, 99 th Annual Meeting, 2010 Matching GOES monthly event data to SID VLF receivers Solar Flare Summary Based on GOES-8 Data September, 2010 A121

37. AAVSO, 99 th Annual Meeting, 2010 Matching GOES monthly event data to SID VLF receivers The importance of collaborating with others to collect and validate data with NOAAs National Geophysical Data Center (NGDC). AAVSO has submitted monthly reports to NGDC since 1980, (for 30 years!), in this format: ID date start max end IR freq AAVSO-ID 40 040101 0320 0343 0323 1 3WC20 A102 40 040101 0539 0605 0543 1+ 1WC20 A102 40 040101 0653 0707 0655 1- 1WC20 A102 40 040102 0944 1003 0947 1 1WC20 A102 40 040103 1809 1823 1811 1- 5AA24 A87 40 040103 1939 2034 1959 2+ 2XX25 A110 ftp://ftp.ngdc.noaa.gov/STP/SOLAR_DATA/Sudden_Ionospheric_Disturbances/

38. AAVSO, 99 th Annual Meeting, 2010 We can detect B class flares recorded by GOES satellites

39. AAVSO, 99 th Annual Meeting, 2010 Evaluating the Importance Rating submitted by SID Observers A121

40. AAVSO, 99 th Annual Meeting, 2010 The importance rating scale is: less than or equal to 18 minutes = 1- 19-25 minutes = 1 26-32 minutes = 1+ 33-45 minutes = 2 46-85 minutes = 2+ 86-125 minutes = 3 greater than or equal to 126 minutes = 3+ Evaluating the Importance Rating submitted by SID Observers NGDC ftp://ftp.ngdc.noaa.gov/STP/SOLAR_DATA/Sudden_Ionospheric_Disturbances/1README.TXT

41. AAVSO, 99 th Annual Meeting, 2010 A Long-Term Project To Set up to: Match Begin, Maximum and End times to GOES events, so that we can: Match the NGDC Importance Ratings to the GOES log scale (A – X) class flares. Work in progress.. Evaluating the Importance Rating submitted by SID Observers A121

42. AAVSO, 99 th Annual Meeting, 2010 Acknowledgements For Helpful Conversations & Encouragement –Joseph DiVerdi, XTR Systems, LLC –Doug Welch, AAVSO-SID, A104 –Mike Hill, AAVSO-SID, A87 –Susan Oatney, AAVSO-SID, A125 –Matt Ettus, GNU-Radio –Peter Wilhelm Otto Arnold Schnoor http://www-star.stanford.edu/~vlf/hail/hail.htm

43. AAVSO, 99 th Annual Meeting, 2010 Questions?

44. AAVSO, 99 th Annual Meeting, 2010 NPM @ Lualualei

45. AAVSO, 99 th Annual Meeting, 2010 NAU @ Aguada, PR

46. AAVSO, 99 th Annual Meeting, 2010 Multi-Channel Observations