The K7VVV Solar Update

SEATTLE, WA, Dec 14, 2001--This has been another relatively quiet week with little in the way of geomagnetic upset. Planetary A indices were in the single digits through Tuesday. On Wednesday the planetary K index went to five, which is quite high, but then quieted back down.

A powerful solar flare erupted Tuesday, but the resulting coronal mass ejection is not Earth-directed. It could cause an upset starting Friday, so the predicted planetary A index for Friday through Monday is 15, 20, 25 and 10.

Average sunspot numbers dropped this week by more than 16 points, and average solar flux was down by almost 3 points. Solar flux is expected to decline, with Friday through Monday values around 220, 220, 210 and 200, and it should reach a short term minimum around December 22-23.

Geomagnetic disturbances could cause problems for the ARRL 10-Meter Contest this weekend, but the effect is difficult to gauge at this point.

Recent 6-meter excitement prompted Rich Zwirko, K1HTV, to send in a report. We won't attempt to summarize, since Rich communicates such excitement over his activities on 6. Rich wrote:

"I just thought I'd let you know how things are going from the mid-Atlantic area on 50 MHz. Although I've on the air with this K1HTV call since 1958, I've only operated 6 meters in the tail end of Cycle 21 in 1981, Cycle 22 (1989-91) and the present Cycle 23. Although the last solar cycle with its double peak was a great one for 6-meter DX, this one (also with a double peak) is even greater. Part of it is because there are more off-the-shelf rigs with 6 meters in them, part of it is because so many countries in Europe have freed 50 MHz from TV use.

"On 6 meters I run about 150 W output to a 6-element Yagi on the roof, 30 feet above the ground. The K1HTV QTH in Glenn Dale, Maryland, is about 12 miles northeast of the White House. To give you an idea of how good the conditions have been here, I've listed below the 74 countries worked so far this year on 6 meters, 70 of them since October 21!

"The prefixes of the 70 countries worked, in the order they are listed are W, VE, VP8 (Falklands), LU, PY, KP4, C6A, GM, PA, G, ON, GW, DL, OK, GI, GM, CO, EA8, YV, VP5, EA, CT, VP9, GB, YU, CU, E3, EA9, PY0, EI, I, 9H, OH, HK, 9Y, FR, D4, IS, 9G, LZ, YU, 9A, TI, OA, FG, SM, OZ, Z2, LA, KL7, GD, GU, OX, TF, OY, ES, OE, LX, C3, V7, HC8, SV, YO, JY, 4X, XE, TG, 5B, UY, SP, ER, Z3, HB0 & OD5. Wow! I can't believe it myself, but they are all in the log, and the QSLs are already coming in. Six meters . . . the Magic Band."

Sunspot numbers for December 6 through 12 were 226, 200, 218, 225, 224, 154 and 183, with a mean of 204.3. The 10.7-cm flux was 246.7, 225.9, 220.5, 224.2, 219, 220.6 and 236.7, with a mean of 227.7. Estimated planetary A indices were 8, 5, 5, 3, 4, 4 and 12 with a mean of 5.9.

Amateur solar observer Tad Cook, K7VVV Seattle, Washington, provides this weekly report on solar conditions and propagation. This report also is available via W1AW every Friday, and an abbreviated version also appears in The ARRL Letter. Readers may contact the author via k7vvv@arrl.net.

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