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[19659002] The region of lower intensity of the Earth's magnetic field, located above the South American continent, has effects that can be felt at a hundred kilometers of altitude. 
When the International Space Station (ISS) ) orbiting the Earth, she crosses her territory, astronauts on mission to the station report d & # 3 9 strange visions: explosions of light, like fireworks. speaking of the Magnetic Anomaly of South America (AMAS), a region of lower intensity of the Earth's magnetic field, located above South American territory, whose most obvious effects can be felt in a hundred kilometers altitude.
was identified a century ago and, although it affects the operation of artificial satellites – with economic and human impact – the anomaly is little known and does not receive attention
In an interview with BBC News Brazil, three researchers from the National Institute of Space Research (INPE) in São José dos Campos (SP) explain in turn the phenomenon – and why it interests us . If you like football, it's worth reading until the end.
"The Earth is surrounded by a magnetic field internal to the planet and protects us from everything that comes from space," says physicist Antônio Lopes Padilha.
This magnetic field, explains Padilha, is generated in the liquid core of the Earth, thousands of kilometers deep. The core is formed mainly of iron and nickel.
"The movement of these electrons generates an electric current and this current generates the Earth's magnetic field."
"The movement of these electrons generates an electric current and this current generates the Earth's magnetic field." The magnetic field is however not the same on all the surface of the planet. In some areas it is stronger than in others.
[19659002] Imagine if the communication satellite failed to transmit right now? Satellites are much more vulnerable to particle precipitation when they traverse the Magnetic Anomaly of South America (Photo: Press / Fox Networks Latin America) The anomaly of South America, historically called the South Atlantic Anomaly, is the region of least intensity of the magnetic field at the surface of the Earth, "says Padilha.
" It covers a much of the South American continent. Its presence brings certain phenomena, especially in the so-called ionosphere region, above 100 km altitude. "
The dimensions of this" hole "vary depending on the altitude, explains the Inpe team
500 km from (the approximate orbit of the Space Station International), the AMAS zone extends between -50 ° and 0 ° of geographical latitude and -90 ° and + 40 ° of longitude, that is to say, in a rough calculation, the An anomaly would be around 90 million square kilometers
Periodically, sudden changes in the magnetic field of the Sun cause the sudden release of large amounts of energy.These phenomena, known as explosions solar, release electromagnetic radiation that propagates at the speed of light in 8 minutes, and also accelerate the particles of the Sun, which can generate so-called magnetic clouds, or Coronal Mbad Ejections (EMC). moves in space, reaches the Earth.
There are particles – pro tons and electrons.This is a mbad of plasma that takes between one and three days to reach the Earth and, when it does, it causes magnetic storms, leading to the precipitation of these highly energetic particles on the planet .
"The most beautiful effect of storms When there is a dawn, we can do a search, a few days before the solar explosion," says Brazilian engineer and doctor of space science Clézio Marcos De Nardin , Director General of the Brazilian Space Weather Program., Embrace / INPE
As the magnetic field that protects the Earth from these particles is weaker in the AMAS region, when there are solar explosions, the risks that the energetic particles released by the Sun cross the magnetic field are much larger
Result: anomalous satellites are much more affected by radioactive particles – and require additional protection.
satellite satellites that cross the planet. An anomaly is much greater here than anywhere else in the world, except for the northern lights, "says De Nardin.
" We know, for example, that Austrian satellites are extinguished when they enter the magnetic anomaly and are reconnected when they exit at the other end. This is done to avoid problems in the computer devices because such a particle can damage the computer or change the attitude of the satellite, leading to its loss. "
Here is what happened to the Japanese Hitomi satellite, explain the researchers." 19659005] "It was an X-ray satellite, an astrophysical satellite. He went into the anomaly and he suffered so much particle bombardment that he was lost. He began to turn around the tree himself and crashed. Then the Japanese Space Agency came to the public to explain why she had lost the satellite. They did not take into account the predictions of space weather, which predicted the arrival of magnetic clouds, which would increase the precipitation of particles in the anomaly, "says De Nardin.
To our knowledge, the man, the importance of abnormality Magnetic resonance imaging is badociated with the potential risks that it presents for the satellite network of the planet – explains the scientist
And as modern societies rely more and more on artificial satellites for multiple activities: communications, navigation, meteorology, defense. , Earth observation and exploration of the Universe – the search for strategies to overcome the anomaly is becoming more and more vital.
"Since about ten years, we have developed a lot of climate forecasts in the space," says De Nardin. The Embrace program, led by him, is one of the five largest in the world to predict space weather.
Predicting space weather is important for the entire planet – but it is fundamental
At AMAS, what is at stake is the large number of satellites that circulate in the area or are stationary there .
"For example, it is around the geographical equator that most communication satellites and other geostationary meteorological satellites reside," De Nardin explains. The protection of this equipment is critical.
The planes are more affected by the anomaly., Never reaches such an altitude. "
Yet, there are ongoing studies on the subject, adds the physicist and PhD in Space Geophysics Marcelo Banik de Pádua
"There is current research, trying to measure the effects (AMAS) on avionics, but we do not expect to find any relevant variations. Rmal having a higher dose in flight because you are taller and you have less atmosphere to protect yourself. It is also expected that the doses are a little higher in our region (under an anomaly), nothing very impressive, but it is what we want to measure. "
It is known that the effect is great at high altitude – for example, on the International Space Station
When the ISS pbades into the anomaly region, it is common that the astronauts see bursts of light, like shooting stars – even when they have their eyes closed
"
A possible explanation for this phenomenon is that the optic nerve, deep in the eye of the eye. astronaut, would be affected by the particles that precipitate it.
During the pbadage of the ISS
In other words, a solar explosion occurred, if the time of arrival of the cloud of particles coincides with the pbadage of the ISS into the anomaly, the odds that they will rain particles on to after De Nardin
"There is an armored room of the I & # 39; ISS for astronauts who will remain during CME's arrival forecasts – hence the importance of
"If there is extravehicular activity at the space station, then 39; that is, if the astronaut leaves the ship to make repairs or experiments – and coincide with a magnetic storm at this time, the astronaut will be much more vulnerable. "
De Nardin points out that solar explosions – and hence magnetic storms – are still a risk for the ISS and his team
" Shortly after a solar explosion, the first particles to arrive are those that were accelerated out of the sun immediately after radiation, they are so violent that they were baptized "
" They can cross the armor of the ISS like a knife cuts the butter , they can cross the electronic circuits, burn their memory, hit the embedded instruments, destroy the computer processors, it is the "brain" of the ISS. "
De Nardin says that in his lectures, a common question is: what effect would the anomaly have on humans – especially in Brazil? [19659005]" In principle, the precipitation of particles does not occur. would not directly affect people here. "
But there is at least one kind of possible impact. "Because the average citizen is more and more connected to the world in real time, let's take the # 39 example of the Russian World Cup and imagine that the Brazilian national team fired shots at the last match. "Do you want the communications satellite to stop transmitting right now?"
"Yes, if you have a magnetic storm and that it is not prepared, and if there is no other satellite" This could be a reality, "concludes the researcher.
