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One of the biggest threats to the world’s telecommunications infrastructure is large emissions of radiation and magnetic energy from solar flares and coronal mass ejections (CME), also known as solar storms. As human civilization has become more and more dependent on the internet and technological infrastructure, the rare occurrence of severe space weather events has posed a much larger threat to industry and human civilization as a whole than ever before. Researcher Abdu Jyothi of the University of California, in her research paper, termed the impact of a solar superstorm event as the ‘Internet Apocalypse,’ where she examines the worst-case scenario of global internet outages from damaged electronic systems caused by rare solar superstorms.

The unique behaviour of the sun’s magnetic field gives rise to the ejection of radiation, particles, and matter from the surface of the sun, called space weather. The sun is made up of plasma, which is an extremely hot gas of ionised particles. The magnetic field of the sun is created in a system which is called the solar dynamo [2], where the motion of the electrically charged plasma in a magnetic field induces a current, which in turn generates more magnetic field [10]. Astrophysicists have deduced the shape of the magnetic fields at the surface of the sun by examining the motion of the plasma in corona loops in the sun’s atmosphere.

Image 1: Corona loops of plasma at the surface of the sun

Sunspots are regions of relatively lower temperatures on the surface of the sun where very strong magnetic fields prevent heat from within the sun from reaching the surface. In these regions, strong magnetic fields become entangled and reorganized. This causes a sudden explosion of energy in the form of a solar flare often accompanied by a coronal mass ejection, which is the ejection of electrically charged solar matter from the sunspot [3].

Some of the electromagnetic energy released by the flares, in the form of x-rays, and ejected particles can reach the earth. However, the earth has its own protective mechanisms against the regular occurrence of mild solar flares and CMEs. The upper layers of the earth’s atmosphere absorb the influx of x-rays. The earth is also surrounded by its own magnetic field, called the magnetosphere, which acts as a protective shield against the ejected solar matter from a CME that reaches the earth. Therefore, telecommunication infrastructure on the surface of the earth avoids the harmful effects. However, telecommunications satellites and GPS satellites further away from the earth’s surface are left more exposed and have been damaged or rendered inoperable due to solar flares [4]. Human health can also be compromised by direct exposure to harmful radiation and high energy particles emitted due to solar activity. On the surface of the earth, we are shielded from the harmful effects of space weather, however, astronauts in space must use special protective gear due to the extra exposure.

One of the positive side effects of space weather interacting with the earth is the spectacular display of the aurora borealis, more commonly known as the northern or southern lights, where charged particles become trapped in the earth’s magnetosphere and accelerate towards the earth’s poles. They collide with atoms and molecules in the earth’s atmosphere, releasing a burst of light and a colourful display in the night sky [5].

Image 2: The deflection of coronal mass ejections by the earth’s magnetic field

Image 3: The Aurora Borealis

More worryingly, there is the unlikely chance of a large-scale coronal mass ejection striking the earth in its direct path causing widespread damage to electrical infrastructure even on the surface of the earth. Such an event has been named a ‘solar superstorm.’ The enormous ejection of electrically charged solar matter causes shock waves in the magnetosphere and releases its energy toward the earth in a geomagnetic storm. As the earth’s magnetic field varies, electric currents are induced on the earth’s conducting surfaces by electromagnetic induction. These are called geomagnetically induced currents (GIC) [1]. This, in turn, induces electrical currents in the power grid and other grounded conductors, potentially destroying the electrical transformers and repeaters which keep the power grid running and damaging the vast network of long-distance cables which provide internet.

There has also been growing concern about the weakening of the earth’s magnetic field over the past few centuries, with some physicists believing it is because of the long overdue flip of the earth’s magnetic poles, something which occurs around every 200,000 years, but has not happened in over 750,000 years. This could potentially leave humans and telecommunication infrastructure on earth more exposed to more moderate and frequent space weather events.

The last large-scale geomagnetic storm, called the Carrington Event, was recorded in September 1859. Its main impact was on the mode of telecommunication at the time, the telegraph network, with reports of telegraph wires catching fire, electrical shocks, and messages sending even when it was disconnected from power. The CME was so strong that auroras could be seen from as far south as the Caribbean! In March 1989, magnetic disturbances caused by a strong solar storm wiped out the entire electrical grid in the Canadian province of Quebec [7]. Of course, since 1859, modern civilisation has become very dependent on electrical infrastructure to provide homes and businesses with power and internet for our constant connectivity demands, so a storm on the scale of the Carrington Event could have catastrophic implications for the world’s economy and society in general. A study by the National Academy of Sciences estimated that the damage caused by a Carrington-like event today could cost over $2 trillion and multiple years to repair [8]. By analysing the records of solar storms over the past 50 years, Peter Riley of Predictive Sciences inc. calculated that the probability of such an event happening in the next 10 years is 12%.

So what can be done to minimise the damage caused by a large-scale geomagnetic storm? As the sun is just coming out of a period of inactivity in its solar cycle, we have not experienced a significant solar storm to test the resilience of modern technological infrastructure against such events. However, nowadays we have a series of satellites which monitor solar activity, such as NASA’s Advanced Composition Explorer [9], which gives forewarning of a large incoming solar storm that would take at least 13 hours to reach earth. This gives power grid operators enough time to shut down their stations and minimise damage caused as it passes. Even with this precaution, an unprecedented Carrington-like event will likely cause widespread damage to the earth’s telecommunications and internet infrastructure, so better damage prevention and recovery plans will need to be put in place to ensure the maintenance of vital technological systems that the world’s population depends so heavily on.

 

References

[1] Sangeetha Abdu Jyothi. 2021. Solar Superstorms: Planning for an Internet Apocalypse. In ACM SIGCOMM 2021 Conference (SIGCOMM ’21), August 23–27, 2021, Virtual Event, USA. ACM, New York, NY, USA, 13 pages. https: //doi.org/10.1145/3452296.3472916

[2] NASA. 2022. Understanding the Magnetic Sun. [online] Available at: <https://www.nasa.gov/feature/goddard/2016/understanding-the-magnetic-sun>.

[3] Spaceplace.nasa.gov. 2022. Sunspots and Solar Flares | NASA Space Place – NASA Science for Kids. [online] Available at: <https://spaceplace.nasa.gov/solar-activity/en/>.

[4] Encyclopedia Britannica. 2022. How solar flares can affect the satellites and activity on the surface of the Earth. [online] Available at: <https://www.britannica.com/video/183276/overview-solar-flares>.

[5] NASA. 2022. Aurora: Illuminating the Sun-Earth Connection. [online] Available at: <https://www.nasa.gov/aurora>.

[6] Raeng.org.uk. 2022. [online] Available at: <https://www.raeng.org.uk/publications/reports/space-weather-full-report>.

[7] NASA. 2022. The Day the Sun Brought Darkness. [online] Available at: <https://www.nasa.gov/topics/earth/features/sun_darkness.html>.

[8] Science.nasa.gov. 2022. Near Miss: The Solar Superstorm of July 2012 | Science Mission Directorate. [online] Available at: <https://science.nasa.gov/science-news/science-at-nasa/2014/23jul_superstorm/>.

[9] O’Callaghan, J., 2022. New Studies Warn of Cataclysmic Solar Superstorms. [online] Scientific American. Available at: <https://www.scientificamerican.com/article/new-studies-warn-of-cataclysmic-solar-superstorms/>.

[10] Paul Bushby, Joanne MasonUnderstanding the Solar Dynamo. Astronomy & Geophysics, Volume 45, Issue 4, August 2004, Pages 4.7–4.13. https://doi.org/10.1046/j.1468-4004.2003.45407.x

[11] Youtube.com. 2020. Could Solar Storms Destroy Civilisation? Solar Flares & Coronal Mass Ejection [online] Available at: <https://www.youtube.com/watch?v=oHHSSJDJ4oo>.

Image Sources

Image 1: Vatican Observatory. 2022. Coronal Loops on the Sun – Vatican Observatory. [online] Available at: <https://www.vaticanobservatory.org/sacred-space-astronomy/coronal-loops-on-the-sun/>.

Image 2 & 3: GoOpti low-cost transfers. 2022. Aurora Borealis: where to see the Northern Lights in 2021?. [online] Available at: <https://www.goopti.com/en/about/goopti_blog/aurora-borealis-where-to-see-the-northern-lights-in-2020>.

What are Coronal Mass Ejections?

Coronal mass ejections, or CME’s, are huge bubbles of plasma with embedded magnetic fields that are ejected from the surface of the Sun [1]. These CME’s contain billions of tons of coronal material and can travel as fast as 3000 km/s (1% the speed of light) as they expand and shoot through space. These are among the most powerful explosions in our solar system, along with solar flares, which erupt with the power of 20 million nuclear bombs. Solar flares and CME’s are often associated with each other as they sometimes occur together, however there has been no definitive relationship established between the two phenomena [2].

The cause of coronal mass ejections is not fully understood, however most scientists agree that the main cause is due to fluctuations in the Suns magnetic field [3]. As the Sun is fluid and is affected by turbulence, its magnetic field can become tangled and kinked which can catapult huge amounts matter out into space. As CME’s are ejected in all directions, most of them are not aimed directly towards us, but occasionally they do impact Earth. The frequency of CME’s vary with the activity of the Sun, which changes over an 11 year period [4]. At periods of high activity (solar maxima) the size and recurrence of CME’s increases, which can have huge effects for us on Earth.

CME’s and the Northern Lights

The Earth’s magnetosphere shields the planet from harmful solar particles such as those produced in CME’s and prevents the erosion of the atmosphere by the continuous flow of charged particles from the Sun, known as the solar wind. Because of the constant bombardment of the magnetosphere by this solar weather, it is compressed on the side facing the Sun and extends into a long tail on the dark side of the Earth [5]. Some of the charged particles can reach the Earth’s atmosphere at the poles, guided by Earth’s magnetic field lines, and interact with oxygen and nitrogen in the upper atmosphere. These interactions produce the commonly known phenomenon of aurorae, which typically form 80 to 500km above the surface [6]. Large coronal mass ejections that reach Earth can create major geomagnetic storms and cause these amazing aurorae to expand away from the poles towards the equator.

 

Image taken by ESA astronaut Alexander Gerst of aurora from the International Space Station on Aug. 29, 2014. Image Credit: NASA/ESA/Alexander Gerst

How would a large CME affect Earth?

A particularly large CME could have major consequences for us on Earth, especially in relation to technology. The potentially huge disruption to Earth’s magnetic field could induce electric currents causing power surges, which could blow out transformers and cripple the electrical grid. Although the Earth’s atmosphere protects us from the dangerous radiation that accompanies them, unprotected astronauts in space would be at a much greater risk.  Furthermore the electronics onboard satellites in orbit could be damaged, causing huge disruptions to communications networks and GPS systems. This would effectively halt the transportation network due to the complete shutdown of air traffic communications. The largest recorded solar storm occurred in 1859, known as the Carrington Event [7]. This storm induced huge currents in electrical circuits, leaving many telegraph lines in North America inoperable. The storm also caused aurorae to be seen as far south as Hawaii and the Caribbean.

Studying Solar Activity

Due to the huge risk that coronal mass ejections pose to the way of life of our modern, technology-dependent civilisation, astronomers study the Sun in order to be more prepared for a large solar event. An impending coronal mass ejection impact can be spotted using a special type of telescope called a coronagraph. The coronagraph blocks out the main bright light of the Sun using a circular shade called an occulting disk. This allows the weaker detail of the corona to be observed. CME’s that are directed towards Earth are called halo events and can be observed using these coronagraphs, which could provide us with the necessary time to plan shutdowns to protect essential communications networks and the electrical grid. Halo events get their name from their appearance, as the ejected coronal matter appears to surround the Sun like a halo as it approaches Earth. Halo event coronal mass ejections usually reach Earth in around two to four days, giving time for scientists to plan an appropriate response.

 

Illustration of CME in the direction of Earth. The blue lines illustrate the arrangement of earths magnetic field as a consequence of solar weather. Image credit: ESA

In summary, large CME’s have the potential to wreak havoc on our modern technology by affecting communication networks and electrical circuits which have far-reaching effects in all aspects of life. As we approach the next expected solar maximum in 2025, with the predicted increase in solar activity and the frequency of CME’s, it is important for us as a civilisation to watch this Space…

 

Written by Thomas Jones.

References

[1]. The Heliopedia. NASA. (2022). Retrieved 11 May 2022, from https://www.nasa.gov/mission_pages/sunearth/the-heliopedia.

[2]. Coronal mass ejection – Wikipedia. En.wikipedia.org. (2022). Retrieved 11 May 2022, from https://en.wikipedia.org/wiki/Coronal_mass_ejection.

[3]. Coronal Mass Ejections | NOAA / NWS Space Weather Prediction Center. Swpc.noaa.gov. (2022). Retrieved 11 May 2022, from https://www.swpc.noaa.gov/phenomena/coronal-mass-ejections.

[4]. What Is the Solar Cycle? | NASA Space Place – NASA Science for Kids. Spaceplace.nasa.gov. (2022). Retrieved 11 May 2022, from https://spaceplace.nasa.gov/solar-cycles/en/.

[5]. Crockett, C. (2022). What is a coronal mass ejection? | Space | EarthSky. EarthSky | Updates on your cosmos and world. Retrieved 11 May 2022, from https://earthsky.org/space/what-are-coronal-mass-ejections/.

[6]. Aurora | NOAA / NWS Space Weather Prediction Center. Swpc.noaa.gov. (2022). Retrieved 11 May 2022, from https://www.swpc.noaa.gov/phenomena/aurora.

[7]. Klein, C. (2022). A Perfect Solar Superstorm: The 1859 Carrington Event. HISTORY. Retrieved 11 May 2022, from https://www.history.com/news/a-perfect-solar-superstorm-the-1859-carrington-event.

[8] Space Weather Research Explorer: CMEs. Exploratorium.edu. (2022). Retrieved 11 May 2022, from https://www.exploratorium.edu/spaceweather/cme.html.