The National Office of Oceanic and Atmospheric Administration (NOAA) monitors space weather, including solar storms and coronal mass ejections and has warned that this week our planet was going to be hit by several “mild and moderate” geomagnetic storms that is unlikely to cause any harm here on Earth. Of course, one of the striking consequences of these energetic flares is that auroras appear further south than usual (they are generally visible around the poles).
When charged particles from the Sun hit Earth’s atmosphere, they are funneled along Earth’s magnetic field lines toward the poles, where they rain down into the upper atmosphere and interact with molecules there. This encounter ionizes the molecules and makes them glow: this is what we know as aurora.
The Sun continues with its ‘noisy’ behavior
According to NOAA, last week’s solar flare resulted in a moderate geometric storm, and this disturbance in conditions is expected to continue for a bit longer.
Coronal mass ejections are large discharges of plasma and magnetic fields from the solar corona and can be emitted in any direction , so they sometimes directly hit the planet of origin.
That doesn’t mean we have to worry ; in fact, we’ve already been hit by mild and moderate geomagnetic storms in recent days, registering G1 and G2 on the five-level solar storm scale ( G5 being the most extreme level ). Although they do cause some degradation in high-frequency radio signals at high latitudes and there may be fluctuations in the electrical network, the consequences will not end here. Yes, it is possible that, if the conditions are right, the satellites end up falling from the sky, but not a probability considered for geomagnetic storms these days.
They are very common?
Earth experiences more than 2,000 G1 and G2 category solar storms every decade , according to NOAA, and is currently in the midst of a mild solar storm streak; the last G2 storm skimmed past Earth on Sunday (March 13), passing by early in the morning without much trouble. And several mild geomagnetic storms occurred on Monday and Tuesday (March 14 and 15) after the outburst of a mild solar flare several days ago.
While extreme geomagnetic storms are rare (NOAA’s Space Weather Prediction Center says we expect four per 11-year solar cycle), minor and moderate geomagnetic storms are much more common .
“There are many types of flares on the sun. Solar flares and coronal mass ejections both involve gigantic bursts of energy, but are otherwise quite different. Sometimes the two phenomena occur at the same time , in fact the strongest flares almost always correlate with coronal mass ejections, but they emit different things, look and travel differently, and have different effects near the planets. ”, explains NASA.
So far in 2022 we’ve seen our fair share of outbursts from our star, and while life here on Earth hasn’t been greatly affected, conditions in orbit have been somewhat chaotic. For example, during the month of February, dozens of Starlink satellites from Elon Musk’s company were hit by a geometric storm shortly after launch, deflecting them and causing them to end up burning in the Earth’s atmosphere.
We have three years to go until the next solar maximum, so more events like these are expected in the near future, although it is unknown if they will escalate in dangerousness beyond a G2 event. Solar minimum occurs when the Sun’s magnetic field is at its weakest and occurs when the Sun’s magnetic poles switch places (the most recent was in December 2019). Solar maximum will occur, in principle, in July 2025, the time when solar storms and CMEs (coronal mass ejections) are most active, so satellite operators, power utilities and other vendors must start making preparations to increase shielding around sensitive equipment or even move satellites.
Reference: NOAA / NASA
