venerdì 28 febbraio 2020

The K7RA Solar Update

Still no sunspots through all of February, except for the first day of the month. I keep watching for possible sunspot activity over the solar horizon on . Recently I noticed a promising looking white area, and in the past few days at they pointed out two new regions just over the horizon.

As of Thursday night, both areas still appear to be transitioning over the horizon at -90 degrees shown on the STEREO monitor at the above URL. But so far nothing in the daily 45 day forecast of solar flux shows any associated increase related to this.

Average daily solar flux changed slightly from 70.9 to 70.5 over the recent week, and geomagnetic indicators remained quiet.

Predicted solar flux over the next 45 days is 70 on February 28 through March 3, and 71 on March 4 through April 12.

Predicted planetary A index is 5 on February 28 through March 3, then 12, 12 and 8 on March 4-6, 5 on March 7-14, then 10, 8, 10, 8, 5, 10 and 8 on March 15-21, then 5, 8, 12 and 10 on March 22-25, 5 on March 26-30, then 20, 15 and 8 on March 31 through April 2, then 5 on April 3-12.

Geomagnetic activity forecast for the period February 28 to March 25, 2020 from F.K. Janda, OK1HH.

Geomagnetic field will be
quiet on: March 11-14
quiet to unsettled on: March 1-3, 15, 18, 21, 23-25
quiet to active on: February (28-29), March 7-10, 19-20, 22
unsettled to active on: March 4-6, 16-17
active to disturbed: NONE!

Solar wind will intensify on: February (28 -29), March 5-7, (17-22).

Parenthesis means lower probability of activity enhancement.

Interesting article about the Kodaikanal observatory in India with some nice butterfly diagrams and charts of daily sunspot area:

Next weekend the Apache Point Observatory in Sunspot, New Mexico hosts an open house:

Solar activity and whale navigation:

And the New York Times weighs in:

Mike Schaffer, KA3JAW, in Easton, Pennsylvania monitors 11 meters for evidence of sporadic-e skip. On Monday, February 24 he reports: “Sporadic-e lasted for nearly three hours from 9:58 AM (1458 UTC) to 12:49 PM (1749 UTC).

“At first, stations were coming from the west with signals from Illinois, Indiana, and Ohio. The furthest was a station in Chicago at 650 miles.

“Half-way into the activity, at around 11:33 am (1633 UTC), sporadic-e changed directions toward the south with signals arriving from Mississippi, Florida, Georgia, Tennessee, and Kentucky. The furthest signal during that round came from Jackson, Mississippi at 1013 miles.”

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Sunspot numbers for February 20 through 26, 2020 were 0, 0, 0, 0, 0, 0, and 0, with a mean of 0. 10.7 cm flux was 70.8, 71.2, 70.2, 70.1, 70.2, 70.6, and 70.1, with a mean of 70.5. Estimated planetary A indices were 8, 14, 9, 5, 4, 3, and 4, with a mean of 6.7. Middle latitude A index was 5, 10, 7, 4, 3, 3, and 3, with a mean of 5.