G1 Storm Watch: Incoming Solar Wind / Big Coronal Hole in the Sun's Atmosphere
A G1 (Minor) Geomagnetic Storm Watch has been issued for 18 January 2017 (UTC Day) due to the anticipated arrival of a polar-connected, positive-polarity CH HSS.
A solar wind flowing from a middle latitude coronal hole will soon become geoeffective. Sky watchers at higher latitudes should be alert for visible aurora beginning Wednesday.
Incoming Solar Wind. A wide hole in the sun's atmosphere is spewing a fan-shaped stream of solar wind toward Earth. NASA's Solar Dynamics Observatory photographed the canyon-like structure on Jan. 15th.
"Coronal Hole" (CH) is a region where the sun's magnetic field opens up and allows solar wind to escape. Material is flowing from this coronal hole at speeds exceeding 600 km/s (1.3 million mph). The high-speed stream could spark G1-class geomagnetic storms when it arrives on Jan. 18-19. http://www.spaceweather.com/
Solar activity was at low levels with an isolated B2 flare observed at 14/0716 UTC from Region 2626. The region was little changed during the period. Region 2625 underwent trailer spot decay.
Both visible regions are currently stable and do not appear to be very threatening. http://www.solarham.net/
Clips, images credit: NOAA/SWPC, NASA/SDO & spaceweather.com
