A new and gigantic coronal hole has just opened in the Sun. It is the size of thirty earths and will cause the arrival, this very weekend, of a veritable avalanche of charged solar particles, which will give rise to category G1 geomagnetic storms and G2, that is, of medium intensity.
As reported by the NOAA (National Oceanic and Atmospheric Administration) Space Weather Prediction Center, the wave of solar particles, which is already hitting our planet, could exceed 600 km/s in speed, “and will continue until the 25th of March”. Despite its spectacular nature, say the scientists, its main effects will be limited to the appearance of northern lights at unusual latitudes.
“The current coronal hole – Alex Young, from NASA’s Division of Heliophysical Sciences, explained to Insider – is between 300,000 and 400,000 kilometers in diameter. And that’s between 20 and 30 Earths lined up one behind the other.” NASA astronomers detected the hole on March 20, when a huge dark spot appeared in the southern half of the Sun’s outer atmosphere.
Coronal holes, despite their name, are not true empty holes, but cooler, and therefore darker, areas in the sun’s atmosphere. When these ‘holes’ open up in the corona (the Sun’s upper atmosphere), they allow a greater flow of the stream of charged particles, a phenomenon we know as the solar wind. That stream of particles is blasted into space at high speed, and according to NOAA, the current hole is unleashing winds traveling at more than 2 million km/h.
Aurora borealis
When these particularly strong solar gales collide with Earth, they can compress the planet’s magnetic shield and trigger events called ‘geomagnetic storms’, often capable of causing electronic devices to malfunction, radio blackouts or even power outages. But also spectacular northern lights far away from the places where they usually occur.
During the last months, and as it approaches its maximum, which is expected in 2025, the Sun has been increasing its activity. For example, NASA’s Solar Dynamics Observatory (SDO) recently detected a gigantic ‘tornado’ spinning through the solar north pole.
For the past few days, scientists have already been watching the Sun’s boiling plasma rise high above its surface, reaching a maximum height of 14 Earths, around 120,000 kilometers on March 18. Two days later, the gigantic coronal hole appeared. The effects of the storm are already being felt today, Friday, and will continue at least until tomorrow. Fortunately, this time it is not expected to cause significant damage.