On 7th June 2011, the Solar Dynamics Observatory (OSD) satellite recorded a medium-size Solar Flare. The event was confirmed by Coronagraphs captured by the Solar Heliospheric Observatory (SOHO). The graphs showed masses of plasma and high energy particles radiating from the Sun at 1400 km per second.
Is the Sun waking up from “The Quiet Before The Storm” as we get closer to the “Unprecedented Solar Storm” predicted by NASA for 2012?
The solar flare mapped to Sunspot complex 1226 and 1227, resulted in a spectacular Coronal Mass Ejection (CME) and a minor radiation storm. The large mass of particles was lifted off the surface of the Sun to fall back again responding to its colossal gravitational force. It spread almost half of the diameter of our star.
In 2006 the Sun went utterly quiet, a period known as Solar Minimum. Sunspots had all but vanished and solar flares were practically non-existing; an unusual event that alarmed scientists, aware of the cyclic nature of our dynamic star.
Sunspots are a measure of solar activity. During Solar Minimum there could be as little as 10 spots observed per year. At Solar Maximum, this number can reach up to 201, as recorded in 1958, the largest in history.
The effects on our planet did not go unnoticed at that time, as testified by newspaper reports:
"Radio blackout cuts US off from the rest of the world. Aurora visible in Los Angeles, Tulsa, Boston, Seattle, Canada and Newfoundland. Voltages in electrical telegraph circuits exceeded 320 volts in Newfoundland. Intense red glow gave way to curtains and shimmering draperies" (New York Times, February 11, 1958, p. 62).
"Although not seen over New York, it was so intense over Europe that people wondered about fires and warfare" (New York Times, February 12, 1958, p. 16).
"Aurora borealis again seen here" (The Washington Post, February 11, 1958, p. A1).
Studies of the Sun’s behaviour have shown that it has an 11-year cycle of sunspots in addition to a conveyor belt of electrically conducting gas that flows in a loop from the Sun’s equator to its poles. This conveyor belt takes between 30 to 50 years to circulate and as it flows, it refreshes the appearance of periods of sunspots. The belt was turning relatively fast between 1986 and 1996, calculations since then point to an increase in surface activity between 2011 and 2013.
Coronal Mass Ejections (CME) and high speed stream of solar wind coming from a Co-rotating Interaction Region (CIR) result in Geomagnetic Storms. These are shock waves of solar wind that cause a disturbance to Earth’s Magnetosphere.
Solar wind is composed of electrons, protons and a few heavier ions that blows continuously from the surface of the Sun, travelling at an speed of 400 km/second. This wind causes a loss of mass of more than 1 million tons per second but this is insignificant in relation to the total mass of the Sun.
Effects of a Geomagnetic Storm
In 1989, a severe Geomagnetic Storm caused the collapse of Hydro-Quebec power grid, leaving six million people without power for nine hours. Generators and Transformers have been known to heat up and even shut down. Power generating companies can minimize damage by momentarily disconnecting transformers and inducing temporary blackouts in response to alerts from the Space Weather Prediction Centre.
In 2003 the “Halloween Sun Storm” caused severe damage to Japanese satellite ADEOS-2 and interrupted other satellites. Global Positioning Systems could be affected with scintillation of signals and unreliable readings.
Radio signals are most sensitive to solar storms, in particular short wave broadcast below 30 MHz (ground to air, ship to shore, amateur and shortwave broadcast), not so television and commercial radio broadcast. Telephone lines, including undersea cables can be affected, with exception of fiber-optic lines.
Although the Earth’s atmosphere and the magnetosphere provide adequate protection to humans, astronauts outside the atmosphere could be at risk if only protected by a space-suit. Depending on the duration of the magnetosphere disruption, biological navigation systems like those of migratory birds and aquatic mammals could be affected.
Changes in the magnetosphere produce Aurorae that could be seen far away from the magnetic poles, even as far as the equator.
The Earliest Records
The effects of fluctuating solar activity are far from new to us. The earliest record of a solar storm or “Solar Superstorm” occurred in 1859, when two global aurora borealis events made the headlines of the time. The sunspot changes reported by Richard Christopher Carrington became known as the Carrington Super Flare.
"Aurora Borealis" - Early this morning, between twelve and one, a most brilliant display of the above phenomenon was observed extending from the western hemisphere to the north-west, north and north-east, and reaching to the zenith. The appearance in the west was that of a large fire, but in the north and north-east it was of a violet colour, and with great brilliancy. This beautiful display lasted for about an hour, and then gradually died away, leaving a serene and unclouded autumnal sky (The London Daily News. P. 2).
The Aurora Borealis"-From twilight until ten o'clock last night the whole heavens were lighted by the aurora borealis, more brilliant and beautiful than had been witnessed for years before….The light streaks shot upwards from the horizon and varied in width and length, and changed as long as the phenomenon was visible. It was a grand sight, and was witnessed by thousands of persons, many of whom never saw the like before (The Baltimore Sun, 1859, p.1).
”The City's Change of Weather” … Towards half past eight o'clock a singular phenomenon took place. The horizon from north to north east became of a deep crimson hue, which expanding slowly, made the sky appear as if lighted by a Bengal fire…At first it was supposed that some great conflagration had taken place on the outskirts of the city, but it was soon recognized that no natural firs could produce this particular hue…Crowds of people gathered at the street corners, admiring and commenting upon the singular spectacle. Many took it to be the sign of some great disaster or important event, siting numerous instances when such warnings have been given. Several old women were nearly frightened to death, thinking it announced the end of the world, and immediately took to saying their prayers. A fat old citizen tremblingly stated that this was the avant courier of a dreadful epidemic like cholera of 1833, whilst a French gentleman pooh-poohed, and gravely assured us that this was the well known sign of a revolution in Paris, requesting us to make a note of the date (New Orleans Daily Picayune, p.5).
In the past 10 million years there have been around 30 magnetic field reversals, periods during which the protection of the magnetosphere was minimal allowing solar particles to reach the atmosphere. During that time, human evolution has followed its course and there is a good chance it will continue to do so despite temporary inconveniences.
References
¤ ‘August – September 1859’ (Unknown date). Space Weather. [Online]. Available here. (Accessed: 17 June 2011).¤ ‘Fire in the Sky’ (1999). Extract from New Scientist Magazine. [Online]. Available here. (Accessed: 17 June 2011).
¤ ‘Geomagnetic Reversal’ (2008). ASKaPHYSICIST on YouTube. [Online]. Available here. (Accessed: 17 June 2011).
¤ ‘Geomagnetic storm’ (2011). Wikipedia. [Online]. Available here. (Accessed: 17 June 2011).
¤ ‘The Solar Wind’ (2011). Dept. of Physics and Astronomy, University of Tennessee. [Online]. Available here. (Accessed: 17 June 2011).
¤ ‘Solar storm of 1859’ (2011). Wikipedia. [Online]. Available here. (Accessed: 17 June 2011).
¤ ‘Solar Storms’ (Unknown date). Space Weather. [Online]. Available here. (Accessed: 17 June 2011).
¤ ‘Solar Storm Warning’ (2006). NASA. [Online]. Available here. (Accessed: 17 June 2011).
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