(Signs in the Sun) Solar Storm Watch: Two Large Holes in the Sun’s Atmosphere
G1 (Minor) Geomagnetic Storm Warning Valid Jan. 27-28. A G1 (Minor) geomagnetic storm warning is in effect for 27-28 Jan. due to influence from the anticipated, positive-polarity coronal hole high-speed stream. Solar Wind Speed: 617 km/sec. Solar Wind Magnetic Fields: Bt 4 nT, Bz -3 nT
Two Large Holes in the Sun’s Atmosphere. NASA’s Solar Dynamics Observatory is now tracking two large holes in the sun’s atmosphere. One is now directly facing Earth, and the other is still turning toward us.
These are “coronal holes” (CHs)–places in the sun’s atmosphere where the sun’s magnetic field opens up and allows solar wind to escape. Coronal holes turn the sun into a kind of gassy lighthouse. They strobe Earth with streams of solar wind every 27 days, the rotation period of the sun. Earth will encounter solar wind streams from both of these holes.
The first is alreaADY HERE. The second, larger stream should reach our planet on or about Feb 1st. Arctic sky watchers should be alert for visible auroral displays.
Sunspot Genesis. A new sunspot group big enough to swallow Earth is bubbling up through the solar surface.
At the time sunspot AR2629 poses no threat for strong solar flares; its magnetic field is too stable for such explosions. However, this could change if its development proceeds apace.
In recent months sunspot numbers have plummeted as the solar cycle crashes toward a new and deep Solar Minimum expected in 2019-2020.
So what is this sunspot doing here? It’s a reminder that the sun can produce spots at all phases of the solar cycle. Individual sunspots are completely unpredictable and may appear without notice at any time.
Even during the great Maunder Minimum of the 17th century, a handful of sunspots were typically observed each year. This is important because sunspots produce solar flares. As a result, occasionally Solar Minimum explodes with solar flare activity.