A geomagnetic storm is expected to blast Earth tomorrow after the sun fired a plume of plasma and high-energy particles toward our planet.
The incoming coronal mass ejection (CME) was unleashed on Sunday at 5.40pm ET when an enormous sunspot spontaneously erupted.
The spout of solar plasma is currently rocketing toward our planet at over 650,000 miles per hour and expected to reach Earth by midday Eastern Time on Wednesday (5pm UK, 2am AEST).
Earth could experience a minor geomagnetic storm by midday Wednesday
But the CME will only glance off the planet’s magnetosphere, or the region of space around a planet dominated by its magnetic field.
Normally, this slight blow wouldn’t trigger a geomagnetic storm. But because it will arrive so close to the fall equinox – which occurred on Sunday – NOAA has forecasted a minor G1 storm for tomorrow.
NOAA’s Space Weather Prediction Center classifies geomagnetic storms on a scale that ranges from G1 to G5 – with G1 being ‘minor’ and G5 being ‘extreme.’
A G5 storm can significantly disrupt infrastructure, causing power and communication blackouts across wide areas.
We won’t have to worry about that with this upcoming G1 storm, however. This type of storm only has a slight risk of impacting infrastructure at high latitudes, including cellphone towers and satellites.
But it could trigger dazzling auroras along the horizon of US states on the northern border and upper Midwest states, according to NOAA.
The G1 storm could trigger dazzling aurora in northern states on Tuesday and Wednesday night
Aurora are typically most active between 10pm and 2am, and you will want to get as far away from light pollution as possible to get a clear view
The fact that this storm is set to occur just days after the fall equinox is no coincidence.
During the weeks before and after Earth’s two equinoxes, geomagnetic storms are more common.
That’s because during equinoxes, the sun sits directly above Earth’s equator and our planet’s magnetosphere becomes aligned with the sun’s magnetic field.
During the rest of the year, they are misaligned, which means that CMEs are partially deflected by the magnetosphere and we do not experience their full impact.
But if a CME occurs while the Earth is experiencing equinox, it clashes more directly with the planet’s magnetosphere and causes geomagnetic activity, even if the CME is weak or an indirect hit.
Conversely, geomagnetic storms are much less likely around the time of the solstices – when the Earth’s vertical tilt toward or away from the sun is at maximum.
Geomagnetic storms are about twice as likely around the time of equinoxes than they are around the time of solstices.
Residents of northern states should keep an eye out for aurora Tuesday and Wednesday night. They are typically most active between 10pm and 2am, and you will want to get as far away from light pollution as possible to get a clear view.
