(Araucaria) Propagacao: Baile funk no sol.

[DXer]

Strong (G3) Geomagnetic Storm Conditions Reported
05/28/2017

NOAA’s Space Weather Prediction Center (SWPC) said strong (G3) 
geomagnetic storm conditions occurred overnight. The SWPC issued a G3 
alert at 0419 UTC on May 28, due to activity associated with a coronal 
mass ejection (CME) on May 23.

“Although the solar wind speed is relatively slow, the embedded magnetic 
field had a prolonged period of southward Bz (a magnetic field 
component) that is causing the geomagnetic activity,” the SWPC alert 
said. Moderate (G2) and strong (G3) storm warnings were valid until 0900 
UTC on May 28, and the forecast calls for only a slight chance of minor 
storming for the remainder of May 28.

The geomagnetic activity generated aurora borealis displays that were 
visible along the northern tier of the US, including the upper Midwest 
and parts of Northern New England. A G3 storm can affect the electric 
power grid, cause intermittent HF radio conditions and affect satellite 
navigation as well as low-frequency navigation systems. In such 
conditions, aurora displays have appeared as far south as 50° 
geomagnetic latitude. It also can increase drag on low-Earth orbit 
satellites.

Spaceweather.com reported that the CME hit Earth’s magnetic field on May 27.

“At first, for several hours, the seemingly weak impact barely disturbed 
our planet’s magnetic environment,” Spaceweather said. “Then the storms 
began. As Earth passed through the CME’s wake, energetic particles 
poured through a crack in Earth’s magnetosphere, sparking strong 
G3-class geomagnetic storms and bright auroras.”