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The K7RA Solar Update

01/20/2012

New sunspot groups appeared on every day over the past week. On January 12, new sunspot group 1396 appeared, and the next day two more -- 1397 and 1398 -- popped into view. On January 14, four new sunspot groups appeared: 1399, 1400, 1401 and 1402. January 15 saw group 1391 vanish and new group 1403 emerge. Two more appeared January 16 -- 1404 and 1405 -- while 1397 vanished. On January 17, 1406 appeared and 1395 disappeared, while 1407 emerged on January 18.

The average daily sunspot numbers rose this week, from 90.6 to 116.9, while the solar flux stayed about the same, changing from 134.9 to 133.4. Sunspot numbers for January 12-18 were 57, 81, 145, 141, 120, 152 and 122, with a mean of 116.9. The 10.7 cm flux was 116.8, 124.1, 132.3, 133.5, 139.7, 139 and 148.1, with a mean of 133.4. The estimated planetary A indices were 5, 6, 3, 3, 8, 5 and 4, with a mean of 4.9. The estimated mid-latitude A indices were 5, 8, 3, 4, 8, 4, and 4, with a mean of 5.1.

The latest prediction from USAF/NOAA has a solar flux of 150 on January 19-20, 155 on January 21-22, 160 on January 23-25, 155 on January 26, 140 on January 27-29, and 135 on January 30-February 6; we are still looking for a solar flux peak of 165 on February 17-21. The predicted flux values of 160 on January 23-25 are markedly higher than the 145 predicted last week for the same dates. The predicted planetary A index is 6, 8, 5, 8 and 12 on January 19-23, and 5 on January 24-February 1, and then 5 on February 5-8.

Roger Larson, KF6IVA, of Harrison, Maine, wrote and referred to errors in the solar article in The Atlantic which was linked from last week’s Solar Update. I think perhaps he is referring to the article’s statement that “Hydrogen, the lightest element and the Sun’s primary constituent, fuses to become helium, releasing energy.”

Roger wrote: “The Sun converts 600 million tons of hydrogen to 596 million tons of helium every second. The missing 4 million tons of matter are converted to energy by E = mc^2. The Sun is approximately 4.6 billion years old and will live another 4.6 billion years as a yellow main sequence star. The Sun has become about 30 percent more luminous since it began burning hydrogen (the faint Sun paradox). The Earth’s early atmosphere had more greenhouse gases, which allowed the surface temperature to be warm enough for life to form. It is also thought that in 100 million years or so, the Sun will become more luminous and may cause the Earth’s temperature to become too hot to support life. Currently, the greenhouse gases raise the surface temperature about 60 degrees F. In 4.6 billion years, the core of the Sun will run out of hydrogen, the Sun will begin to swell and the helium in the core will fuse to carbon and oxygen. The Sun may swallow the Earth in its giant phase, which will last about 1 billion years. The Sun will never go supernova (it does not have enough mass), nor will it be able to burn carbon or oxygen. It will puff off its outer envelope and become a white dwarf.”

We mentioned a Belgian website in this bulletin one year ago on January 22, 2010. If you click on the “Solar Activity” link toward the top and select “Sunspot Regions” from the drop-down menu, it takes you here. When I see this early Friday morning (1145 UTC), it lists seven regions (sunspot groups) in the table and gives the number of sunspots in each.

You may recall from past bulletins that the daily sunspot number is calculated by multiplying the number of regions by 10 then adding 1 for each sunspot. As there are 7 regions and 47 spots, the sunspot number would be 70 plus 47, or 117. When I look here, I see that the sunspot number for January 19 is 117.

If you click on the image of the Sun to the left of the table, it takes you here where you can find details and recent images for each sunspot group. You can also see details on these here. Note the daily reports are shown with the date for the following day. So the January 19 report was issued in the early part of January 20, so it gets a January 20 date. Note the Space Weather Live site offers an aurora alert via e-mail.

On Wednesday, Science Daily published a brief article on the Solar Dynamics Observatory.

Charlie Carroll, K1XX, of Grant, Florida (on Florida’s East Coast, about 70 miles southeast of Orlando), notes that the ARRL CW DX Contest is February 18-19, right in the midst of that period (February 17-21) in which NOAA predicts solar flux values of 165. He is looking forward to operating PJ4X in Bonaire for the contest, so he is watching this prediction closely.

Jon Jones, N0JK, of Wichita, Kansas, wonders if a solar flux value of 165 in February is a bit too optimistic. He also wonders if Solar Cycle 24 will have two peaks like Solar Cycle 23, the first peak being in November 2011. Jon notes there was some good 6 meter sporadic E skip on Wednesday night (Thursday January 19, UTC time) around 0420-0530 UTC from Kansas and Colorado into Mexico, and “East Coast stations had E-skip to C6 with link on to Brazil, Argentina and Chile.”

There seems to be energy from a solar flare headed our way; however, on Thursday, the prediction for January 19 showed the planetary A index rising to 10 on Saturday (January 21), 8 on Sunday, and 10 again on Monday. That doesn’t seem like a large effect, but perhaps Friday’s forecast will be more dramatic.

MSNBC has a piece on the flare and National Geographic does, too. Also, check out Universe Today. As always, www.spaceweather.com/ has frequent and timely updates. On Thursday, they said the flare was at 1630 UTC on January 19 and came from sunspot group 1401, and mentioned an impact centered on 2230 UTC on Saturday, January 21, with an ambiguity of plus or minus seven hours.

Vic Alfonsi, WA6MCL, of Corona, California, was on 18.074 MHz running 100 W on CW into a dipole at 1750 UTC on January 14. He said he “was in QSO with Mitch NH6JC/M while he was in his vehicle watching the Sun rise over the water on Kauai. He had good signal, usual 17 meter stuff, very strong but little signal meter reading. Very low S/N. Many Midwest stations were calling him. After I finished the QSO with Mitch, Bill, K2TQC, called him and although very strong here in Corona, it was hard to copy. I quickly realized that he had a very strong echo. His signal from Syracuse, New York was 599 and his 1.5 second delay echo was 589. I moved him off frequency and he confirmed same on me. I know in previous reports that you mention that on 80, but I have never heard that before on 18 MHz. His info says he runs power and loops, so he was not using a beam.”

Vic thinks he and Bill may have heard both long path and short path signals.

Victor Paul, WB0TEV, of Greenville, Texas, sent a link to the same geomagnetic observatory from where until recently, we received weekly geomagnetic forecasts. Unfortunately, the retiring staff member (F. Zloch) was the one who actually wrote the predictions we used. Upon his recent retirement after 34 years, nobody there is doing the same predictions. At the link, you can see local K index readings but the only predictive function is the remark for the following day, such as “Quiet” or “Unsettled to Active.”

All times listed are UTC, unless otherwise noted.

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 each Thursday in The ARRL Letter. You can find a guide to articles and programs concerning propagation here. Check here and 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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