The coronal hole in the Sun spurred NOAA to issue an alert for geomagnetic storms.
This week, NASA astronomers spotted a gaping, black region on the sun. The so-called “coronal hole” looks as if someone blew a hole right through our star, and its appearance spurred NOAA to issue an alert for geomagnetic storms.
The “hole” isn’t really a hole, but rather is a large region much cooler than the rest of the Sun, causing it to appear black. As explained by NOAA in its alert on Wednesday, the dynamics of the coronal hole were expected to speed up the solar winds, and so the agency warned of minor-to-moderate geomagnetic storms as a result, falling under the classifications G1 and G2 (on a scale that goes all the way up to G5).
This coronal hole is simply massive. According to Insider, it’s the size of 20-30 Earths. “The current coronal hole, the big one right now, is about 300,000 to 400,000 kilometers across,” Alex Young from NASA Goddard’s Heliophysics Science Division told the outlet. “That is about 20-30 Earths lined up back-to-back.”