Sun Fires 'Solar Storm Train' at Earth—Three Direct Hits for Weekend

A particularly volatile sunspot has sent a series of solar storms surging toward the Earth, many of which are due to hit in the next few days.

Sunspot AR3663 released five plumes of solar plasma—coronal mass ejections, or CMEs—in the past day, with the second, third, and fifth being forecast to slam directly into our planet this weekend.

This could lead to "strong" geomagnetic storms in our magnetic field and atmosphere, which could result in auroras being seen as far south as Illinois and Oregon.

"It's a #solarstorm train! We now have FIVE storms headed towards Earth! Storm 2, 3, and 5 will be direct hits as seen in the coronagraph imagery. Impacts start around midday May 10 and will continue through late May 12 at least. G3-level conditions & extended #aurora possible," space weather physicist Tamitha Skov posted to X, formerly known as Twitter, early on Thursday morning.

CMEs and solar flares are released from sunspots on the sun's surface, which are dark spots caused by regions of intense magnetic field activity. A solar flare is a burst of solar radiation, usually X-rays, while a CME is a cloud of solar material flung out into space. The sunspot responsible for these recent CMEs has also spat out several powerful solar flares in recent days, including an X4.5-class flare on May 6, which triggered radio blackouts across the Indian Ocean.

"These flares occur when the magnetic fields on the sun become twisted. The magnetic fields can break, causing solar flares that are electromagnetic storms on the surface of the sun," Roger Dube, a professor of physics at the Rochester Institute of Technology in New York, told Newsweek.

"These are huge by Earth standards, about the size of a planet, and the electromagnetic effects can be intense even as far as Earth. Sometimes these flares cause a massive amount of solar plasma to be emitted into space in the form of a Coronal Mass Ejection, or CME,"

When a CME hits the Earth's magnetic field, it can trigger geomagnetic storms, which are classed based on their strength on a scale of G1 (minor) to G5 (extreme). These are caused by the charged particles of the CME colliding with the Earth's magnetosphere, causing complex changes in the magnetic field.

There are around 200 G3 storms per 11-year solar cycle, while there are only about 100 G4 storms and four G5 storms in the same period. More powerful storms become more common towards the solar maximum, which is the period during the solar cycle when the sun is most active. We are currently approaching the solar maximum, which is due to occur between now and the start of 2026.

The CMEs on their way to Earth are due to hit on May 10, 11, and possibly 12, and are expected to result in geomagnetic storms between G1 and G3 in strength.

Geomagnetic storms can have a number of impacts on Earth, ranging from voltage issues with electronics and radio blackouts to increased drag on satellites.

"[CMEs] travel into the interplanetary region, and if it encounters the Earth, we see Space Weather storms that can knock out satellites and affect communications and the power grid. These are usually accompanied by the Northern Lights, which are emitted as the charged particles from the sun pass through the Earth's magnetic field," Dube said.

More powerful geomagnetic storms may also lead to brighter and unusually far-reaching northern and southern lights. G5 storms can result in auroras being seen as far south as Florida and southern Texas.

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