On March 13th, the SOHO coronagraph, a solar telescope, registered an extreme coronal mass ejection or CME in English. The plasma cloud was ejected from the sun at a speed of over 10 million kilometers per hour, which is an unusually high speed – an extreme CME that occurs maybe once or twice over a few decades. The normal speed for an ejected plasma cloud/CME is otherwise around 2 million kilometers per hour.
The American space agency NASA’s simulations show that the CME was so strong that it created a shockwave in all directions. As Earth was in the exact opposite direction this time, the impact was weak but sufficient to knock out radio traffic on and around both the North and South poles. Although the plasma cloud was ejected from the far side of the sun, away from Earth, the GOES-16 satellite from the U.S. government’s scientific organization, the National Oceanic and Atmospheric Administration (NOAA) found that some of the particles still reached Earth. This further demonstrates how extreme the CME was, and we can conclude that it would have led to catastrophic consequences if it had been directed towards Earth.
Several days after the solar eruption on March 13th, radio traffic on and around the poles continued to be affected. This is because our planet’s magnetic field consists of power lines that run from the magnetic North Pole to the magnetic South Pole. The magnetic field extends tens of thousands of kilometers into space and forms the magnetosphere there. As a result, particles are “diverted” towards the poles, which are more weakly protected, which is why we see auroras in these areas. Warnings were issued, and for three days, shortwave radio in the area was mostly completely knocked out, severely affecting air traffic in the area.
Once again, an unexpected geomagnetic storm
On March 11th, a very weak CME occurred on the sun, which this time was directed towards us. It was so weak that it normally should not have affected Earth at all, but to many people’s surprise, it still caused a geomagnetic storm when it hit Earth on March 15th. Initially classified as a minor G1, it was later upgraded to a moderate G2. This is considerably more alarming than the extreme CME on the sun’s far side two days earlier, as it reminds us of Earth’s increasingly weakened magnetic field… a weakening that researchers in 2010 realized had accelerated at least tenfold in recent decades.
As a consequence, New Zealand once again experienced celestial displays in the form of southern lights, and in Europe and North America, as far south as the USA, people experienced northern lights. That they could be seen simultaneously on March 15th in both hemispheres is due to the time of year. It was just six days before the March equinox, known as the vernal equinox in the Northern Hemisphere and the autumnal equinox in the Southern Hemisphere, which this year falls on March 20th. Almost equal darkness allows sky watchers in both hemispheres equal opportunities to witness auroras, which are caused by particles from the sun hitting Earth’s upper atmosphere, causing oxygen to glow red and green, and nitrogen to shine purple. A beautiful spectacle at the same time as it is an extremely ominous omen for those who understand that auroras for the second time in such a short period would not have been so spectacular and visible so far from the poles if it were not for Earth’s weakened magnetic field – a disaster-inviting process that is also accelerating.