‰ Now 18 WPM transition file follows ‰

Geomagnetic activity was down quite a bit from last week, but solar
wind and a south pointing Interplanetary Magnetic Field late
Wednesday left Earth vulnerable. The mid latitude K index reached 4,
and the planetary K index rose to 6. The IMF is from our Sun, and
the point where it contacts earth magnetic field is called the
magnetopause. Earths magnetic field protects us from solar wind, and
the Earths magnetic field at the magnetosphere usually points north.
But when the IMF points south, it is opposite Earths magnetic field,
and the two link up. This carries energy from the Sun directly into
the Earth, and this can cause aurora and geomagnetic instability.
This is generally bad for HF radio propagation. The IMF continues to
point south on Thursday evening, and this could leave Earth
vulnerable to a coronal mass ejection erupting on the Sun on
Wednesday at 2230z. The wind from this event is traveling at about
3R36 million miles per hour, or 1500 km per second. Sunspot numbers
were 76, 57, 91, 99, 88, 68 and 48 with a mean of 75R3. 10R7 cm flux
was 92R4, 93R2, 92R1, 89R8, 89R2, 86, and 84, with a mean of 89R5.
Estimated planetary A indices were 24, 11, 7, 7, 9, 4 and 36 with a
mean of 14. Estimated mid latitude A indices were 18, 5, 4, 5, 5, 3
and 17, with a mean of 8R1‚

‰ End of 18 WPM transition file ‰