A coronal mass ejection occurs when the Earth’s outer atmosphere, or corona, experiences a solar flare. The corona is the part of the sun that emits rays and spreads warmth and light to the Earth. During a solar flare, part of the Earth’s outer atmosphere is emitted into space. During particularly large solar flares, huge explosions are occurring which cause balloon-shaped clouds of solar wind to rise over the corona, expanding as they rise. These clouds are referred to as coronal mass ejections or CMEs.
During a CME, very, very hot plasma, which is heated to tens of millions of degrees, creates superheated protons, electrons, and nuclei. Electrons flowing along the magnetic field flow faster than the solar wind, which includes all of the plasma flowing along. These fast flowing electrons can create an electric shock which pushes particles forward at very high speeds, sometimes up to 2 million miles per hour.
When this ejection is directed towards Earth, it can trigger disturbances in the Earth’s space weather, or the upper layers of its atmosphere. Whether it will affect Earth and how much depends on the direction it is heading towards among several other factors. Of the CMEs that head toward Earth, some will have a greater affect on Earth’s activity than others. The factors influencing the effect a Coronal Mass Ejection will have on Earth include the amount of material that is ejected, the speed at which the ejection is traveling, and the strength and direction of its magnetic cloud, that is the electrons traveling ahead of the solar wind.
CMEs create the aurora borealis and aurora australis, the northern and southern lights. These are created by the reaction between the ejection and the Earth’s atmosphere. This interaction forms a kind of electrical generator which drives particles of its mass further down into the lower layers of the atmosphere. The atmosphere dissipates a small portion of the particles in light, which is viewed as the northern or southern lights depending on which end of the Earth it is viewed.
The solar flare activity only lasts for a few hours in space, but the affects of the ejection of solar mass on Earth can last far longer. An electrical charge can build up in satellites, causing damage to satellite equipment if the equipment is on and transmitting signals. A built up electrical charge can overload the satellite and send the charge to all equipment used in receiving and interpreting the signal. Damaged satellites can lead to difficulty in operating systems that rely on the use of satellites, such as air traffic control systems.
A charge can also be created in long metal structures including power lines or oil and gas lines. The build-up of an electrical charge in power lines can blow transformers if they are not shut down prior to the charge. This can cause large power outages that may take several days to restore. Entire lines may need to be replaced. This can cause a large expense for power companies.
Oil and gas lines can explode if an electrical charge is carried through them. This can not only cause a great deal of damage to the line itself but also to the area surrounding the line. This can incur a great expense, not only in finding a way to repair the line, but also cleaning and restoring any areas that were extensively damaged in the explosion. This can be a hardship for many individuals, because they are not only incurring expenses but losing large portions of profits in the process.
Coronal mass ejections occur during large solar flares, when part of the sun’s outer atmosphere is ejected in large quantities into space. Though not all coronal mass ejections affect the Earth, the ones that do can have long standing consequences. They can generate a great deal of damage, causing inconvenience, as well as adding expense. Many companies employ specialists to analyze the possibilities and probabilities of CMEs in order to better prepare for any impending activity and minimize risk. This goes a long way to minimizing the effect of a CME on Earth.