THE SOLAR WIND IS COMING: A hole in the sun’s atmosphere is turning to face Earth, and it is spewing a stream of solar wind in our direction. NASA’s Solar Dynamics Observatory photographed the structure on Jan. 19th:
This is a “coronal hole”–a region where the sun’s magnetic field opens up and allows solar wind to escape. Emerging faster than 600 km/s, the gaseous material is expected to reach our planet on Jan. 22nd or 23rd.
We’ve seen this coronal hole before. It opened in July 2018 and has been spinning around with the sun, lighthouse-style, lashing Earth with solar wind once a month since then. In late Dec. 2018, it sparked a G1-class geomagnetic storm with strong bursty auroras around the Arctic Circle.