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The K7RA Solar Update

05/25/2018

Sunspot activity resumed this week, after no sunspots for seven consecutive days. Average daily sunspot number was 7.7, rising from 6.4 in the previous reporting week. Average daily solar flux was 70.1, changed little from 70.2 last week.

According to Spaceweather.com, in 2018 56% of days so far have been spotless.

Currently sunspot group 2710 and 2711 are active (2711 is growing), and 2712 is about to emerge beyond the horizon. On May 23 50 one-millionths of the visible solar surface was covered by sunspots. April 24-25 was the last time this level of activity was seen. On April 21-22 the sunspot area numbers were 120 and 130. 

Average daily planetary A index and mid-latitude A index were both 5.3, down from 8.4 and 9 the previous week.

Due to an error at NOAA, the mid-latitude A index for Tuesday was previously reported on Wednesday as 55. This did not make sense to me, as no other magnetometers reported such huge activity. I sent a couple of emails to various contacts at NOAA, and AD0IU got it fixed. This changed both the mid-latitude A index and planetary A index for the day.

Predicted solar flux is 74 on May 25-27, 73 on May 28, 72 on May 29 to June 1, 70 on June 2-6, 68 on June 7-16, 69 on June 17-20, 70 on June 21 through July 3, and 68 on July 4-8.

Predicted planetary A index is 5 on May 25-27, 8 on May 28, then 5 on May 29 through June 1, then 28, 16, 16, 14, 12 and 8 on June 2-7, 5 on June 8-12, 8 on June 13, 5 on June 14-18, then 16, 12 and 8 on June 19-21, 5 on June 22-27, then 16, 26, 16, 14, 12, 12 and 8 on June 28 through July 4, and 5 on July 5-8.

The above solar flux and planetary A index predictions are updated daily at ftp://ftp.swpc.noaa.gov/pub/forecasts/45DF/ 

 

Louis Szondy, VK5EEE, of Findon, South Australia reminds us: “I read with interest the comments of N4KZ on ‘seemingly dead bands’ and I'd like to remind your readers about the beacons that cover the world on the 20, 17, 15, 12 and 10-meter bands. I think many hams either don't know about, or have forgotten about those beacons, or because they are in CW they think it will be hard to know which is which, but thanks to the Internet it is easy: the website shows exactly which beacon is transmitting and where. So, to remind readers, the IBP International Beacon Project has 18 beacons spread out around the world, transmitting for 10 seconds each taking turn, sending call sign and first dah at 100 W, then second dah at 10 W, third at 1 W and 4th dah at 100 mW, in each case to an omnidirectional ground plane antenna. Therefore, once every three minutes the same beacon transmits again on the same frequency. By listening for 3 minutes on 14100, 18110, 21150, 24930 and/or 28200 kHz, it is easy to know which parts of the world are open to your location, and if you do not know Morse code you can see which one is transmitting live on this page, provided your computer clock is accurate. See www.ncdxf.org/beacon.

“Bear in mind that these beacons are 100 W to a ground plane, even two dipoles broadside to each other at a sufficient height, let alone beams, would improve signal strength considerably between yourself and that location.”

 

Mark Lundy, WD4ELG, noted on May 22: "On 20-meter FT8 this evening I copied Russia, Mauritania, Brazil, Hawaii, Alaska, Germany, New Zealand and Australia. Just by calling CQ, I worked New Zealand, Australia, Ceuta, Portugal, Switzerland, Germany, and France. I’m using a Hex beam and 50 W.

“I don’t remember a collection of DX like this at the same time since the late ‘70s. It is probably possible to work DXCC on 20 meters with FT8 in 24 hours. We may lack sunspots, but FT8 has sure brought a lot of hams on the air.”

 

Larry Godek, W0OGH, of Cochise, Arizona wrote on May 20: "Dead bands or poor propagation? There have been some days when the bands were indeed dead. Nothing heard, and it affected 40 and everything above 17 meters here in Arizona during the day.

“I was reading some old 1979 QST magazines the other day, just to refresh my memory of where we came from, and I ran across an article from a Russian ham about HF ducting. Perhaps that is what may have occurred when I recently worked the 3B7A DXpedition on 40-meter SSB. It has happened on other occasions as well, mainly with hard-to-work DX stations. A52SV on 15 meters is another one that comes to mind. 

"With 3B7A, I had one last chance and that was Saturday afternoon and evening. I had been outside working and figured it was time to go check out the bands. Fifteen, 20 and 17 meters had delivered nothing. The 3B7A crew were working 40-meter SSB as usual, so I figured I’d listen for a bit. Pretty soon I wasn't hearing any other stations and they were calling CQ with no response. I gave him a shout, and even though it took three calls, the operator finally came back to me. I was astonished! I run an Elecraft K3 transceiver at 100 W and the antenna was a 40-meter inverted V up about 18 feet fed with 125 feet of LMR-400 cable. 3B7A are confirmed in Logbook of The World as well as Clublog, so I can now relax a bit!

“Yesterday on 20-meter FT8, it was a bonanza for me here in the high desert. I managed to work CT3HF, YT3PL, CT1LT, YB1RUS, YB5BOY, 9K2NO, a bunch of Russian stations, HZ1FI, 3D2AG, VKs, ZLs, numerous JA stations, YB0OHG, FK8DD, VK0AI, BX2AFU, XV9NPS, BD7BS, HP1AVS, S51ZZ, LA1PHA, GM3VFR, OM5XX, and EA9ABC – all while using 50 W and a Yagi at 40 feet.”

 

Geomagnetic activity forecast for the period May 25 to June 19, 2018

Geomagnetic field will be:

Quiet on May 25, 30, June 8-11, 13-17

Quiet to unsettled on May 26, 31, June 7, 12

Quiet to active on May 29, June 6

Unsettled to active on May 27-28, June 3-4, 18

Active to disturbed on June 1-2, (5, 19)

Solar wind will intensify on May (25-27, 31,) June 1-3, (4-8,) 19

Remark:

- Parenthesis means lower probability of activity enhancement.

- Forecasts remain less reliable,

F.K. Janda, OK1HH

 

From Tamitha Skov: "Dear Tad:  This week we get a real treat. A new active region has rotated into view with a magnetic configuration that is twisted up like a pretzel. On the Sun, things that are twisted up usually don't stay that way for long. They release all that tension in a jolting burst of energy. (Sort of sounds like life, doesn't it?) Those jolts of energy are solar flares and they help to reconfigure and relax the solar pretzel. However, they often come with little warning. In less than three days we have gone from a very quiet Sun to one that has fired multiple C-class flares and has us forecasters flirting with the idea of raising the M-flare risk!  On top of that, solar flux has been boosted to levels we haven't seen in months. I've even heard from amateur radio operators, who have told me they are firing up their rigs for the first time in months, excited they might make contacts denied them this entire year!

“In the forecast video this week, I discuss how we are keeping a close eye on this new activity. As anticipated, today NOAA named the new region 2712 (that is why I had it in parenthesis in the video) and they are upping the C-flare risk to 25% for the day. This means we will likely see more flare activity before things settle down. If this region remains active for a few more days, it has the possibility of firing a solar storm while in the Earth-strike zone. Chances for this are slim, but it’s always a possibility. Overall, this is turning out to be a very exciting week!

Cheers, Tamitha"

Her latest weekly video: https://www.youtube.com/watch?v=3TbE7svHfYA&feature=youtu.be

 

For more information concerning radio propagation, see the ARRL Technical Information Service at http://arrl.org/propagation-of-rf-signals. For an explanation of numbers used in this bulletin, see http://arrl.org/the-sun-the-earth-the-ionosphere.

An archive of past propagation bulletins is at http://arrl.org/w1aw-bulletins-archive-propagation. More good information and tutorials on propagation are at http://k9la.us/.

Monthly propagation charts between four USA regions and twelve overseas locations are at http://arrl.org/propagation.

Instructions for starting or ending email distribution of ARRL bulletins are at http://arrl.org/bulletins.

Sunspot numbers for May 17 through 23, 2018 were 0, 0, 0, 0, 12, 12, and 30, with a mean of 7.7. 10.7 cm flux was 69, 69.4, 70.3, 68.8, 69.6, 70.8, and 73.1, with a mean of 70.1. Estimated planetary A indices were 10, 4, 3, 3, 3, 5, and 9, with a mean of 5.3. Estimated mid-latitude A indices were 9, 3, 3, 3, 3, 6, and 10, with a mean of 5.3.

 

 



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