Propagation and Solar Issues

1. Propagation and Solar Issues Carl Luetzelschwab K9LA k9la@arrl.net http://k9la.us TCDXA Oct 2014 K9LA

2. TCDXA Oct 2014 K9LA

3. What We’ll Cover • Update on Cycle 24 • Another Maunder Minimum? • Hints for Working FT4TA Tromelin • What Do the Numbers Mean? • What Bands Are Good? When Are They Good? TCDXA Oct 2014 K9LA

4. Cycle 24 Update • Cycle 24 began in late 2008 • First peak after 3½ years • Second peak after about 6 years – still in progress • We’re still in the second peak • Higher bands should be good this fall/winter TCDXA Oct 2014 K9LA

5. Cycle 24 vs Cycle 23 Will Cycle 24 have a similar long descent to minimum? TCDXA Oct 2014 K9LA

6. Speaking of Minimums . . . • We were used to short minimums – about 2 years • Then the minimum between Cycle 23 and 24 came along TCDXA Oct 2014 K9LA

7. Length of Min vs Next Max The longer the minimum, the smaller the next cycle TCDXA Oct 2014 K9LA

8. Recorded History • Three periods of larger cycles • Two periods of smaller cycles • It looks like we’re headed for a period of smaller cycles TCDXA Oct 2014 K9LA

9. How Small? Another Maunder Minimum? Cycle 1 • Maunder min was a 70-year period of very few sunspots • 1645-1715 TCDXA Oct 2014 K9LA

10. MM Fueled By Mag Field Data • July 2009 paper by W. Livingston and M. Penn • Sunspots are visible when their magnetic field strength is > 1500 gauss • Extrapolating the linear trend line says no sunspots will be visible by the end of the decade (2020) • Is this the signature of a Maunder Minimum? TCDXA Oct 2014 K9LA

11. Update Thru 2013 • Magnetic field strength still decreasing • But it looks like it is starting to level off TCDXA Oct 2014 K9LA

12. Update Thru September 2014 • It sure looks like it’s leveled off • Suggests sunspots won’t disappear TCDXA Oct 2014 K9LA

13. MM Conclusion – For Now! • It’s kind of looking like we’ll just see an extended period of smaller cycles • Not a period of few or no sunspots • We’re going into uncharted territory • The Sun will do whatever it wants! TCDXA Oct 2014 K9LA

14. FT4TA Tromelin • End of October thru early November 2014 • mid point is ~ Nov 5 • They plan to concentrate on the higher-volume bands  • Second priority is the low bands  • Let’s look at propagation from the MSP area to Tromelin TCDXA Oct 2014 K9LA

15. Great Circle Paths from FT4TA MSP FT4TA antipode FT4TA great circle paths in 10o increments TCDXA Oct 2014 K9LA

16. W6ELProp Map • Pretty close to a high latitude path • More sensitive to elevated K and A indices • Short path (red) heading to the NE • Long path (black) heading to the SW TCDXA Oct 2014 K9LA

17. Predictions on the Higher Bands • Black line is monthly median MUF • 50% of the days of the 1-month period centered on Nov 5 • Blue line is monthly median FOT • 90% of the days • White = S8 • Yellow = S7 • Green = S6 • Red = S5 short path 20m – good opportunity from 2200-0300 UTC 17m, 15m, 12m – good opportunity from 1400-2200 UTC 10m – 50% probability from 1600-1900 UTC TCDXA Oct 2014 K9LA

18. Predictions on the Higher Bands • Long path openings are pretty much limited to around and after sunrise • White = S5 • Yellow = S4 • Green = S3 • Red = S2 • Best shots are • 20m: 13-15z • 17m: 14-16z • 15m: 14-16z long path TCDXA Oct 2014 K9LA

19. FT4TA on 160-Meters • Know when the entire path is in darkness (referred to as common darkness) • For stations in the MSP area • MSP sunset is around 2253 UTC • FT4TA sunrise is around 0148 UTC • Approximately 3 hours of common darkness • Watch especially around FT4TA sunrise • Up to a half hour before and a bit after • All this also applies to 80-Meters, and to 40-Meters to a lesser extent TCDXA Oct 2014 K9LA

20. Wedge of Daylight The terminator at FT4TA sunrise superimposed on the terminator at FT4TA sunset All of NA should be able to work FT4TA on 160-Meters (if someone is on at each end!) TCDXA Oct 2014 K9LA

21. Headings to FT5ZM on 160m FT5ZM • FT5ZM – 77 reports from topband operators • 49 true great circle paths, 28 other paths black lines are great circle paths out of FT5ZM For FT4TA, start with short path, but always check other directions TCDXA Oct 2014 K9LA

22. What Do the Numbers Mean? image from www.qrz.com • SFI is 10.7 cm solar flux • Generally the higher the flux, the better the higher bands • But the short-term correlation between daily SFI and daily MUF is poor • SN is sunspot number • Ditto above comments TCDXA Oct 2014 K9LA

23. Numbers - continued • K is 3-hr index • Tells how disturbed the Earth’s magnetic field is • Generally an elevated K index gives lower mid and high latitude MUFs • An elevated K index may enhance low latitude MUFs • 0-9, with 0 = quiet and 9 = extremely disturbed • A is daily average of the eight 3-hour K indices • 0-400, with 0= quiet and 400 = extremely disturbed TCDXA Oct 2014 K9LA

24. Numbers - continued • XRY is x-ray flux at 1-8 Angstroms (0.1-0.8 nm) • B, C, M, X - B is least, X is most • Higher letters indicate more adverse impact to D region • 304A is flux from Sun at 304 Angstroms (30.4 nm) • 26-34 nm ionizes greater than 50% of F2 region • See SFI and SN comments • Aur is auroral activity from NOAA satellite • Roughly correlates to K index • Lat is lowest geographic latitude impacted by auroral event TCDXA Oct 2014 K9LA

25. Numbers - continued • Bz is direction of interplanetary magnetic field (IMF) • +50 to -50, negative indicates south with disturbed conditions • SW is solar wind speed in km/s • Average is around 400 km/s • Much higher values suggest CME or coronal hole • PF is proton flux at geosynchronous altitude • Values of 10 and higher suggest polar cap absorption (PCA) • EF is electron flux at geosynchronous altitude • Values less than 10 suggest disturbed magnetic field TCDXA Oct 2014 K9LA

26. Numbers - continued • MUF Bdr is the MUF over the Boulder ionosonde at the designated time assuming it’s the mid point of a 3000 km path • EME deg is estimated Earth-Moon-Earth path attenuation in words • Band prognosis • Caveat emptor – subjective assessment • Geomag Field is assessment of K index in words • Sig Noise Lvl is estimated noise in S-units due to SW and K • Could be masked by man-made and atmospheric noise • CME (UTC) is estimated time when coronal mass ejection will hit TCDXA Oct 2014 K9LA

27. What Bands? When? • 160m, 80m, 40m are driven by absorption • These bands are best during night at solar min • 15m, 12m, 10m are driven by MUF • These bands are best in daylight at solar max • 30m, 20m, 17m are good throughout an entire solar cycle • Can withstand more absorption than 160/80/40m • Don’t need as high a MUF as 15/12/10m TCDXA Oct 2014 K9LA

28. What Bands? When? • Right now during 2nd peak of Cycle 24 • 15m, 12m and 10m are best • 30m, 20m and 17m are good • 160m, 80m and 40m generally not considered good • But you can still work lots of DX around solar max • Fall/winter of 2015/2016 • 15m, 12m and 10m openings will decrease • 30m, 20m and 17m will be the best bands • 160m, 80m and 40m better • Fall 2016 and onward • 15m, 12m and 10m will be mostly noise • 30m, 20m and 17m will still be good • 160m, 80m and 40m will also be good TCDXA Oct 2014 K9LA

29. Summary • We’re in the second peak of Cycle 24 • It won’t last forever • Take advantage of good propagation on the higher bands now! • Recent data suggests that we’re not headed into another Maunder Minimum • Just a period of small solar cycles • Dust off the low band gear • FT4TA should be very workable on all bands • We are inundated with space weather data • I think it’s too much – but it’s colorful! • In the next several years we’ll transition from the higher bands being best to the lower bands being best TCDXA Oct 2014 K9LA