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When the Hubble Space Telescope pbades through it, its instruments are turned off.
Ignoring it can be fatal. In 2016, a brand new Japanese satellite, the powerful Hitomi, designed to study black holes and clusters of galaxies, infiltrated it inconsiderately and paid the price: it collapsed and shattered in the despair of Japanese astronomers.
When the International Space Station (ISS), in orbit around the Earth, crosses its territory, astronauts on mission at the station report strange visions: explosions of light, such as fires. artifice.
We are talking about 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 may be to be felt at a hundred kilometers altitude.
It was identified a century ago and, although it affects the functioning of artificial satellites – with economic and human impact – the anomaly is little known and does not receive attention deserved by the international scientific community, say Brazilian scientists.
In an interview with BBC News Brazil, three researchers from the National Institute of Space Research (INPE) of São José dos Campos (SP) explain the phenomenon in turn – and why we are interested. If you like football, it's worth reading until the end.
"The Earth is surrounded by a magnetic field internally generated on 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 conditions of the place, where the temperature and pressure are very high, generate a large amount of free electrons that are constantly circulating.
"The movement of these electrons generates an electric current and this current generates the Earth's magnetic field."
The magnetic field, however, is not the same over the entire surface of the planet. In some areas it is stronger than in others.
" It covers a large part of the South American continent. Its presence brings certain phenomena, especially in the region known as the ionosphere, above 100 km altitude. "
The dimensions of this" hole "vary according to the altitude, explains the Inpe team
(the approximate orbit of the International Space Station), the area AMAS extends between -50 ° and 0 ° of geographical latitude and -90 ° and + 40 ° of longitude, that is, in a rough calculation, the anomaly would be around 90 million square kilometers
Periodically, sudden changes in the magnetic field of the Sun cause a sudden release of large amounts of energy.These phenomena, known as solar explosions, release radiation electromagnetic propagation that propagates at the speed of light in 8 minutes, and also accelerates the particles out of the Sun, which can generate what are called magnetic clouds, or coronal mbad ejections (CME). s, reaches the Earth.
There are particles – protons and electrons. a mbad of plasma that takes one to three days to reach the Earth, and when it does, it causes magnetic storms, precipitating these highly energetic particles on the planet.
"The most beautiful effect of magnetic storms is the aurora (polar): when there is a dawn, one can search, a few days before the solar explosion," says the 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 energy particles released by the Sun through the magnetic field are much larger.
Result: satellites experiencing an anomaly are much more affected by radioactive particles – and require additional protection.
"The amount of particles reaching the satellites that go into the anomaly is much greater here than in any other part of the globe, except for aurora regions," De Nardin explains.
"We know, for example, that Austrian satellites are extinguished when they enter the magnetic anomaly and are closed when they go out at the other end. 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. "
This is what is arrived at the Japanese satellite Hitomi, explain the researchers.
"It was an X-ray satellite, an astrophysical satellite." He went into the anomaly and there he suffered so much particle bombardment that he was lost. It began to revolve around the axis and crashed. As the Japanese Space Agency came to the public to explain why they had lost the satellite, they did not take into account the predictions of space weather, which predicts the arrival of a magnetic cloud, which would increase the precipitation of particles in the anomaly, "says De Nardin.
As far as we know, for man, the importance of the magnetic anomaly is badociated with the potential risks that it brings to the planet's satellite network – 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 – seeking strategies to avoid Anomaly becomes more vital.
"In the last ten years, we have developed a lot of weather forecasts in the space," says De Nardin. The Embrace program, led by him, is among the first five in the world to predict space weather.
Predicting spatial weather is important for the entire planet – but it is fundamental near the poles (where magnetic storms can affect energy transmission systems) and the region of magnetic anomaly.
At AMAS, what is at stake is the large number of satellites circulating in the area or stationary there.
"For example, it is around the geographical equator that most communication satellites and other geostationary meteorological satellites reside," De Nardin explains. Protecting this equipment is essential.
"Imagine we do not expect tornadoes in the Gulf of Mexico and the United States?"
Thus, satellite experts use three main strategies to "dribble" the anomaly.
"First, build more robust systems that resist the precipitation of particles." Second, design embedded computers that allow the satellite to run longer without control, with larger internal drives capable of storing More information, control operations do not coincide with magnetic storms (which is done according to the prediction of the space weather), "says De Nardin.
"Are planes much more affected in the anomaly?"
"The plane flies much lower, it never reaches the altitude of it, they reach 10 or 12 km maximum altitude – I am talking about commercial flights. "
However, there are ongoing studies on the subject, adds the physicist and doctor in space geophysics Marcelo Banik of Padua.
"Research is underway, trying to measure the effects (of AMAS) on avionics, but we do not expect to find any relevant variations. that the doses are a bit higher in our area (under the anomaly), nothing very impressive, but that's what we want to measure. "
What the l & # 39; it is known that the effect is important at high altitude – for example, at the International Space Station.
When the ISS crosses the area of anomaly, it is common for astronauts to see bursts of light, like shooting stars – even when they have their eyes closed.
"This does not just happen in the anomaly, but it happens more often," says Banik de Padua.
A possible explanation for this phenomenon is that the optic nerve, deep in the eye of the astronaut, would be affected by the particles that precipitate it.
When the ISS pbades through the AMAS region, the risks badociated with solar explosions also increase.
In other words, a solar explosion has occurred, if the arrival time of the cloud of particles coincides with the pbadage of the ISS in the l 39; anomaly, the chances that they rain particles on the station increase a lot. In this case, the ISS team must be very careful, says De Nardin.
"There is an ISS shielded room for astronauts who stay during CME arrivals – hence the importance of space weather forecast centers like Embrace. / INPE, "he says.
Extra-vehicular activities are prohibited during these periods.
"If there is extravehicular activity at the space station – that is, if the astronaut leaves the ship for repairs or experiments – and coincides with a magnetic storm at that moment, the astronaut will be much more vulnerable. "
De Nardin points out that solar explosions – and hence magnetic storms – still pose a risk to the ISS and its team. But they are much more dangerous when the ISS pbades into the AMAS region.
"Shortly after a solar explosion, the first particles to arrive are those that were accelerated out of the sun immediately after radiation, so violent that they were called" killer particles. "
" They can cross the shield of the ISS as a knife cuts the butter, they can cross the electronic circuits, burn their memory, hit the embedded instruments, destroy the computer processors, 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?
" In principle, the precipitation of particles does not occur. do not directly affect people here. There is no connection to skin cancer, none of that. We are talking about things that are important over a hundred kilometers (altitude). "
But there is at least one type of possible impact." Because the average citizen is increasingly connected to the world by real time, let's take the example of the Russian World Cup and imagine that the Brazilian national team is firing the goal of the last game. said De Nardin.
"Do you want the communication satellite to stop transmitting right now?"
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