By Guy Page

As plentifully reported on Vermont’s social media, the Northern Lights came out last night, providing spectacular multi-colored nighttime views across northern New England.

So far – thankfully – there have been no reports of the aurora borealis hindering Hurricanes Helen and Milton rescue and recovery operations – a possibility predicted yesterday by federal authorities.

The Northern Lights – first studied in 1621 by a French scientist who called them the Aurora (‘light,’ named for the Greek goddess of the dawn light) Borealias (greek word for northern). By any name, they are the visible result of a collision of electrons from a Coronal Mass Ejection (CME) or ‘solar flare’ with the earth’s magnetosphere. 

A fast coronal mass ejection (CME) erupted from the Sun the evening of 8 October. It arrived at a speed of 1.5 million MPH in last night, Wednesday October 10, the Space Weather Prediction Center (SWPC) of the National Oceanic and Atmospheric Administration (NOAA) said yesterday.

It’s the second big Northern Lights Show this year and the first since May. 

Unlike the awful terrestrial storms afflicting the southern U.S., this solar storm is harmless – mostly. However, NOAA says, “This storm could impact ongoing recovery efforts for Hurricanes Helene and Milton in several critical ways”:

Communications: Systems that depend on low-Earth orbit satellites or High-Frequency communication may experience disruptions.

Power grids: The storm could put additional stress on power grids already weakened by the hurricanes.

GPS services: Navigation systems, especially those relied upon in disaster relief, may be degraded.

Starlink and GPS services were degraded in the May storm, and in 2022 solar storm dozens of Starlink satellites were lost. As of this morning, Friday, October 11, neither StarLink nor NOAA nor any other ‘space weather’ source has reported problems related to the Oct. 10-11 Aurora Borealis.

When skies are clear, the aurora (Northern Lights) “could be visible as far south as Alabama and northern California tonight,” NOAA said yesterday. 

The following ‘deep dive’ information is provided by NOAA:

Aurora is the name given to the glow or light produced when electrons from space flow down Earth’s magnetic field and collide with atoms and molecules of the upper atmosphere in a ring or oval centered on the magnetic pole of Earth. The collisions produce light much like how electrons flowing through gas in a neon light collide with neon and other gasses to produce different colored light bulbs.

The Aurora is also called the Northern Lights in the northern hemisphere and Southern Lights in the southern hemisphere. The technical term for the Northern Lights is Aurora Borealis and the Southern lights are called the Aurora Australis. 

What causes the Aurora?

The aurora is formed from interactions between the solar wind streaming out from the sun and Earth’s protective magnetic field, or magnetosphere. The aurora is one manifestation of geomagnetic activity or geomagnetic storms. As the solar wind increases in speed and the interplanetary magnetic field embedded in the solar wind turns southward, the geomagnetic activity will increase and the aurora will become brighter, more active, and move further from the poles. Even moderate solar wind creates aurora so there is usually a weak aurora somewhere even when there isn’t a big geomagnetic storm.

There are two types of solar events that create big geomagnetic storms that are associated with bright and active aurora. The first is a Coronal Mass Ejection, or CME, which can be described as a billion tons of plasma ejected from the sun, traveling at a million miles per hour. When a CME arrives at Earth, it can produce some of the biggest geomagnetic storms and thus, some of the brightest and most active auroras that extend furthest toward the equator. The second solar event that can create moderate sized geomagnetic storms is called a coronal hole. Coronal holes are the source of high speed solar wind streams. When these high speed streams arrive at Earth, they can produce active auroras.  But the geomagnetic storms and aurora associated with coronal holes is less active than those from the biggest and fastest CME’s.