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The K7RA Solar Update

06/05/2009

It is so great to see some real Solar Cycle 24 sunspot activity this week. Instead of a phantom that pops into view one day and is gone the next, we have sunspot 1019, which has persisted for five days so far. Emerging on Sunday, May 31, the resulting daily sunspot numbers through June 4 are 15, 23, 19, 17 and 17. This is a Solar Cycle 24 spot, and at high latitude too -- an indication of a new cycle spot.

Meanwhile, the low solar wind and quiet geomagnetic conditions continue. Currently, spot 1019 is about to fade, although it is still a few days away from crossing the eastern limb to the far side. NOAA and the US Air Force expect geomagnetic conditions to continue to be quiet, and a planetary A index around 5 is predicted until June 29. Predicted solar flux values are 72 for June 5-6, then 74 on June 7-13.

Geophysical Institute Prague predicts quiet geomagnetic conditions June 5-8, quiet to unsettled June 9-10 and quiet again June 11. Sunspot numbers for May 28-June 3 were 0, 0, 0, 15, 23, 19 and 17 with a mean of 10.6. The 10.7 cm flux was 67.7, 68.2, 68.5, 68.5, 72.5, 71.9 and 72.5 with a mean of 70. The estimated planetary A indices were 7, 5, 3, 3, 3, 2 and 4 with a mean of 3.9. The estimated mid-latitude A indices were 5, 4, 2, 3, 2, 2 and 4 with a mean of 3.1.

It's time now to look at our three month average daily sunspot numbers to spot trends. It looks like the numbers are up, slightly. The three month average of daily sunspot numbers for January-April was 2.4, 2.3, 1.5 and 2. The last number -- centered on April -- is the sum of all daily sunspot numbers for March through May, divided by the number of days. Since 2007, the three month moving average has been:

Jan 07 22.7
Feb 07 18.5
Mar 07 11.2
Apr 07 12.2
May 07 15.8
Jun 07 18.7
Jul 07 15.4
Aug 07 10.2
Sep 07 5.4
Oct 07 3.0
Nov 07 6.9
Dec 07 8.1
Jan 08 8.5
Feb 08 8.4
Mar 08 8.4
Apr 08 8.9
May 08 5.0
Jun 08 3.7
Jul 08 2.0
Aug 08 1.1
Sep 08 2.5
Oct 08 4.5
Nov 08 4.4
Dec 08 3.7
Jan 09 2.3
Feb 09 2.1
Mar 09 1.5
Apr 09 2.0

The average daily sunspot number for just the month of May was 4, indicating a nice trend following the March and April three month averages.

David Witkowski, W6DTW, of San Jose, California, was happy to see the reports of nighttime 20 meter propagation from N6CAS, and notes that on May 20 he worked LY1000A (Lithuania) at 0405 UTC, ES1QD in Estonia at 0612 UTC on May 22 and OH5LF (Finland) at 0635 UTC on May 23. He worked them all using 100 W and a vertical antenna. He wrote: "I told some friends here in San Jose that I'd worked Europe barefoot at 11 PM local time and a few of them gave me the 'Oh yeah, sure you did' look. Thanks for vindicating me. Regarding the question of 'dead' versus 'unoccupied' bands, I wrote a blog article recently on this topic. During summer Es, I used to listen to 28.4 and/or tune from 28.3-28.5 to check for openings. Recently, I made the discovery that listening on CB channel 38-LSB (27.385) is a much better way to do a quick check for openings; I have monitored stations from all over the Western US burning up '38 lower' well into late evening, while 10 meters sits idle. Many times there is propagation -- we're just not using it."

Howard Estes, WB4GUD, of Franklin, North Carolina, also likes to check Citizens Band activity for a 10 meter propagation indicator, saying, "I agree with W1ZI -- the bands aren't dead, we're just lazy. How often do you scan a band, don't hear anything and go somewhere else? I've started checking the CB channels for activity. If I can hear the Big Frog Gigger in lower Alabama, 10 meters is probably open to somewhere."

Mark Lunday, WD4ELG, of Hillsborough, North Carolina, wrote about a June 1 Es opening on 6 meters that still continued at 0400 UTC on June 2: "I worked 12 stations on CW and SSB across the Midwest on 6. I also had some multi-hop on 10 meters using WSJT JT65A and heard Oregon. Second night in a row that I was hearing Es late at night on 10 meters using WSJT weak-signal propagation." Mark said he likes to use DX Sherlock.

Bill Turner, W4WNT, of Matthews, North Carolina, has had good luck lately with PSK on 20 meters, even when there are no sunspots. He is running 25 wWatts into a G5RV at 25 feet, and on May 21 at 0345 UTC, he worked Peter, ZL1PWD, who reported working 12 stations that day.

Erik Jacobsen, KB9BNY, of McHenry, Illinois, sent a message saying that PSK31 on 20 meters "has been on fire this week. On Tuesday -- with the sunspot number at 19 and the solar flux at 72 -- 20 meters nicely opened up for worldwide communication. I participate in the PSK reporter network. Basically, when a reporting station receives the de <call sign> <call sign> pattern, the location of the transmitting station is then plotted on a map. When I checked the map on Tuesday morning, I saw a Pakistani station, two New Zealand stations and a Japanese station plotted. It just goes to show you how well 20 meters can perform with a small amount of power (usually under 30 W), a narrow-band signal and relatively modest solar conditions. I preserved the map for historical purposes here. Tuesday's total monitoring take for a 24 hour period was 30 countries. I occasionally blog my PSK reporter observations here. My current PSK reporter map can be viewed here." Thanks, Erik! Great stuff.

Again this week, we have a book recommendation. Bill Scholz, KB1SGY, of Greenwich, Connecticut, advises checking out The Sun Kings: The Unexpected Tragedy of Richard Carrington and the Tale of How Modern Astronomy Began. Bill writes that this is "an engaging book by Stuart Clark that describes, in great detail, how the great astronomers of the 19th century linked sun spots, solar flares, auroras and magnetic storms. An excerpt from the flyleaf: 'In September of 1859, a cloud of seething gas engulfed the Earth and a blood-red aurora erupted across the planet. Around the world, telegraph machines burst into flames, while compasses reeled as if struck by a massive magnetic fist. No one knew what could have released such strange forces upon the Earth -- no one, that is, except the amateur English astronomer Richard Carrington.'"

Bill calls this "a great read and I recommend it highly if you're interested in the connection between these phenomena."

Last week's bulletin mentioned a consumer communications product out of Japan that would require text messengers to learn Morse code. We asked if anyone could decode the Japanese in a graphic on a Web page talking about the product, and Brett Graham, VS6BG, says it is just a banner ad for a television show. He thought the product might be for real, but checked with JA3USA, who thought it was an April 1 joke. But as Brett said, "The idea does have something going for it."

Amateur solar observer Tad Cook, K7RA, of Seattle, Washington, provides this weekly report on solar conditions and propagation. This report also is available via W1AW every Friday, and an abbreviated version appears in The ARRL Letter. Check here for a detailed explanation of the numbers used in this bulletin. An archive of past propagation bulletins can be found here. You can find monthly propagation charts between four USA regions and 12 overseas locations here. Readers may contact the author via e-mail.



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