Science

A geomagnetic storm is brewing, with northern lights visible at unusual latitudes

A solar storm is taking place, and this could cause the Northern Lights to form at lower latitudes than usual. Major space weather agencies have warned that the solar storm would occur from Monday, September 27 to Tuesday, September 28. Its intensity varies from moderate to minor, respectively, for the two dates.

Both the US National Oceanic and Atmospheric Administration (NOAA) and the UK Met Office have released forecasts for the storm, which is believed to be the result of multiple coronal mass ejections (CMEs) and solar winds released by a “gap” that is’ is open in the solar corona.

While there may be up to four CMEs that can affect Earth, there is no need to worry. The storm will only reach level G2, relatively low on the five-level solar storm scale, where G5 is the strongest level ever detected.

A visual spectacle (probable)

At high latitudes, the predicted G2 storm may have caused fluctuations in the power grid, the orientation of the satellites may have been affected, with greater drag in low Earth orbit, and high frequency radio propagation may have weakened.

“The Northern Lights could be observed from New York State to Washington State through Wisconsin,” NOAA writes in its statement. Solar storms are an integral part of normal space weather, and in the next few years we can probably expect to see more of them. They occur when the Sun moves, in the form of EMC and solar winds, causing disturbances in the Earth’s magnetic field and in the upper atmosphere.

During an EMC, the solar corona (the outermost region of its atmosphere) erupts, expelling plasma and magnetic fields into space. If the EMC is oriented towards the Earth, the collision of the solar ejection with the Earth’s magnetic field can cause a geomagnetic storm, also called a solar storm.

Solar winds, meanwhile, emerge from “holes” in the Sun’s corona. These are cooler and less dense regions of plasma in the Sun’s atmosphere, with more open magnetic fields. These open regions allow solar winds to escape more easily, sending electromagnetic radiation into space at high speed. If the hole is oriented toward Earth, these winds can blow directly in its direction, rushing toward our magnetosphere.

Currently, the Sun faces both phenomena. “There are four CMEs that can affect the Earth,” explains the UK Met Office on its website. “Three of these could arrive separately or as a single combined element on September 27, and another CME could reach Earth later on September 27 or 28.”

Solar cycle: more and more frequent eruptions

A fast solar wind could also hit Earth on September 27 and 28, although the effects of this wind are considered uncertain. “There is also a low risk of EMC and fast winds hitting Earth at similar times, which would have a greater effect. Any reinforcement would decrease during September 28 and 29 ”, adds the Meteorological Office.

All charged particles that collide with Earth’s magnetic field are sent along magnetic field lines toward the poles, where they excite or ionize gases in Earth’s upper atmosphere. The ionization of these molecules generates the amazing dancing lights that we call auroras.

According to the auroras forecast from Space Weather, the Kp 6 level could be reached, in the Kp index of ten points of geomagnetic activity. This means that there is a great possibility for the formation of bright and dynamic polar auroras.

We can also expect more solar storms in the coming months and years. In fact, the Sun is currently heading toward the most active period of its 11-year cycle, called the solar maximum. During solar maximum, the solar magnetic field, which controls sunspots (temporary regions of strong magnetic fields), solar flares, and coronal mass ejections, is at its maximum, as is solar activity.

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