Image courtesy: WordlessTec
Importance
>for life
The Earth’s magnetic field is incredibly important, as it is able to deflect the solar wind (a stream of mostly protons and electrons) and hence protect our atmosphere. These charged particles are deflected to the Earth’s poles, giving rise to the notorious Northern/Southern lights. By protecting our atmosphere, it is able to sustain all of life on our planet.
The importance of this apparent ‘shielding effect’ by the magnetosphere was demonstrated by the chance alignment of the Earth with Mars during a passing gust of the solar wind. The loss of oxygen ions from both planets’ atmospheres was measured (as the same solar wind hit them), with the results showing that the loss of oxygen from the Martian atmosphere occurred at 10 times the rate compared to Earth. Without the magnetic field, the solar wind would completely diminish the Ozone layer. This layer prevents harmful ultraviolet radiation from reaching the Earth’s surface, which, if allowed to penetrate, would lead to an increased risk of cancer amongst the world’s population.
The importance of this apparent ‘shielding effect’ by the magnetosphere was demonstrated by the chance alignment of the Earth with Mars during a passing gust of the solar wind. The loss of oxygen ions from both planets’ atmospheres was measured (as the same solar wind hit them), with the results showing that the loss of oxygen from the Martian atmosphere occurred at 10 times the rate compared to Earth. Without the magnetic field, the solar wind would completely diminish the Ozone layer. This layer prevents harmful ultraviolet radiation from reaching the Earth’s surface, which, if allowed to penetrate, would lead to an increased risk of cancer amongst the world’s population.
The Northern lights caused by the solar wind
>for dating
Other important aspects of the magnetic field are based upon the fact that the polarity of such a magnetic force is recorded in sedimentary type rocks. Reversals of the magnetic field are seen as ‘stripes’ along mid-ocean ridges where seafloor spreading occurs, which provide the basis for dating rocks and sediments (magnetostratigraphy). Furthermore, in the geomagnetic poles remaining constant between reversals, it enables us to track the past movements of the continents (paleomagnetism). The field also magnetizes the crust, with magnetic anomalies helping in the discovery of ores.
Biomagnetism
Thу boundary surrounding the Earth acts as a barrier to not only the solar wind but to other solar activity such as coronal mass ejections and solar flares. Under this protective veil, life has been allowed to flourish for millions of years. Without the magnetosphere, the surface of the Earth would be subject to a continuous bombardment of the supersonic, extremely hot solar wind – this environment could not sustain any form of life known to us.
The health and ultimate survival of organisms is in fact dependent on the magnetic field. Whales, pigeons, honeybees and various other animals navigate using the magnetic field (magnetite in sensory cells within the brain that react with the electromagnetic radiation from the field – provides correct orientation). Vegetation is also highly responsive to changes in the magnetic field, as the magnetism activates their cells for germination. The use of the magnetosphere by all mammals for health and survival was exhibited by results obtained from studying the ‘zero field’. This is an area that is not influenced by the magnetic field, and thus its intensity and strength is equal to zero.
A notable study of the ‘zero field’ centered on a group of mice spending four months void of any electromagnetic influences. The results showed that the mice aged at a significantly faster rate compared to age-matched controls that were under normal living conditions (i.e. exposed to the Earth’s magnetic field). The mice also had a higher tendency to form tumors. In addition to this, pathological changes were observed in their livers, leukocytes, kidneys and urinary bladders of the animals.
A further study was related to how the unavailability of a magnetic field lowered the threshold of pain perception. When the body is experiencing pain or suffering from emotional/psychological stress, large quantities of endorphins are released. This endorphin release following injury allows for a greater tolerance of pain. Experiments showed that mice placed in a magnetic field deficient environment produced intolerance to pain (compared to mice under normal conditions). In humans, the negative effects of depriving the body of normal magnetic fields were reversed by providing a weaker field strength (0.5 microTeslas). As this particular response was reversed by Naxolone (a chemical), which blocks endorphins, it proves that the Earth’s magnetic field is responsible for endorphin release in the body.
The health and ultimate survival of organisms is in fact dependent on the magnetic field. Whales, pigeons, honeybees and various other animals navigate using the magnetic field (magnetite in sensory cells within the brain that react with the electromagnetic radiation from the field – provides correct orientation). Vegetation is also highly responsive to changes in the magnetic field, as the magnetism activates their cells for germination. The use of the magnetosphere by all mammals for health and survival was exhibited by results obtained from studying the ‘zero field’. This is an area that is not influenced by the magnetic field, and thus its intensity and strength is equal to zero.
A notable study of the ‘zero field’ centered on a group of mice spending four months void of any electromagnetic influences. The results showed that the mice aged at a significantly faster rate compared to age-matched controls that were under normal living conditions (i.e. exposed to the Earth’s magnetic field). The mice also had a higher tendency to form tumors. In addition to this, pathological changes were observed in their livers, leukocytes, kidneys and urinary bladders of the animals.
A further study was related to how the unavailability of a magnetic field lowered the threshold of pain perception. When the body is experiencing pain or suffering from emotional/psychological stress, large quantities of endorphins are released. This endorphin release following injury allows for a greater tolerance of pain. Experiments showed that mice placed in a magnetic field deficient environment produced intolerance to pain (compared to mice under normal conditions). In humans, the negative effects of depriving the body of normal magnetic fields were reversed by providing a weaker field strength (0.5 microTeslas). As this particular response was reversed by Naxolone (a chemical), which blocks endorphins, it proves that the Earth’s magnetic field is responsible for endorphin release in the body.
Hazards
>impact on human activity
The interaction of solar winds with the Earth’s magnetic field can trigger the development of magnetic storms. These storms can interrupt radio communications, interfere with global-positioning systems as well as disrupt oil and gas well drilling. Furthermore, they can damage and affect satellite operations, cause electrical blackouts by inducing voltage surges in power grids. Airline activity may also be affected. The storm also compromised the operations of various devices like GPS systems and satellite programming.
The solar wind's effect on Earth (image from BBC)
The true, hazardous nature of a magnetic storm was demonstrated on 20th March 1989 (mainly affecting North America). Electrical currents surged into the Earth’s crust, which then made their way into the high-voltage Canadian Hydro-Quebec power grid. This caused the transformer to fail, resulting in over 6 million people being left without power for 9 hours.
>interaction with the Moon
Another dilemma associated with the Earth's magnetic field relates to how the moon passes through the Earth’s magnetic field for four days every month. As a result, the moon’s surface becomes charged with static electricity. This questions the safety of lunar exploration, as the charged surface increases the risk of electrical discharges. These can interfere with and damage sensitive electronic devices used by space exploration teams. Likewise, the surface charging may also affect the behavior of lunar dust, which is known to easily penetrate spacesuits, equipment and the living space of the astronauts.