MORE SOLAR WIND IS COMING: Earth is exiting a stream of solar wind that produced an outburst of auroras on Feb. 16th through 18th. Good news for photographers: The next stream of solar wind is already on the way. It is flowing from this coronal hole, photographed today by NASA’s Solar Dynamics Observatory.
Coronal holes are places in the sun’s outer atmosphere (or “corona”) where the sun’s magnetic field opens up and allows solar wind to escape. The flow of solar wind along “open field lines” is indicated by white arrows in the false-color image above.
Coronal holes are not rare. They open up several times each month. Solar wind flowing from this particular hole could reach Earth on Feb. 23-24. Arctic sky watchers should be alert for auroras on those dates