South Atlantic Anomaly and evolving dent in the Earth’s magnetic field
A fairly well-known phenomenon called South Atlantic Anomaly refers to the unusually weak magnetic field over S. America and the South Atlantic.
A belly in the protective shield sounds scary to any person, but what do scientists say when they say South Atlantic Anomaly? Researchers from the US National Aeronautics and Space Administration (NASA) have recently noticed a growing belly in the Earth’s magnetic field across South America. And the news is caught like a firework in the digital community.
The tooth refers to the weak magnetic field over a particular region of the Earth. But don’t worry, this change is not expected to have a direct impact on people. A fairly well-known phenomenon called South Atlantic Anomaly (SAA) refers to the unusually weak magnetic field over South America and the South Atlantic Ocean. And scientists recognize that this anomaly could pose a risk to spacecraft and satellites.
In addition, recent NASA data show that the belly splits in two and thus evolves into a major threat to future satellite missions.
What is the Earth’s magnetic field?
The planet Earth has a strong magnetic field, and this magnetic property comes from its core, which melts iron and nickel host. You can easily know about its presence with the help of a magnetic compass, which always points north. Earth is equal to a magnetic bar and the north and south poles represent both sides. The invisible magnetic field lines surround the planet between the North and the South.
This magnetic field can extend up to millions of kilometers in outer space. The nucleus is in a constant state of motion about 1800 miles below the surface and this motion helps generate magnetic fields through convection currents that carry a stream of charged particles. Do you remember the school’s popular homopolar motor experiment?
The magnetic field is important because it prevents harmful solar particles from entering the Earth’s atmosphere. Without the protective bubble of the magnetic field, the solar winds can easily damage the entire atmosphere and biosphere of Earth. Moreover, it also protects the satellites orbiting the Earth from the harmful radiation. The lack of a strong atmosphere over Mars is also attributed to the lack of a magnetic field to protect its surroundings.
South Atlantic anomaly
Per NASA, the South Atlantic Anomaly arises from two main functions – the tilt of the Earth and the flow of molten metals within the outer core.
The Sun displaces a constant outflow of particles and magnetic fields, known as the solar wind. The magnetic fields are aligned with a pair of donut-shaped belts, known as the Van Allen radiation belts. These cloud-shaped belts specifically trap the charged particles flowing through the solar wind and help to repel the particles from the earth’s magnetic field. The belts form part of the magnetosphere – the area of space where the earth’s magnetic field meets solar wind.
As per NASA, when the strong storm of particles from the Sun reaches Earth, the Van Allen belts can become very energetic and the magnetic field can be deformed, allowing the charged particles to penetrate the atmosphere. This is what is happening across South America and the South Atlantic Ocean.
At present, the SAA has no visible impact on daily life on Earth’s surface. However, tracking the anomaly is crucial to the proper functioning of our satellites and digital communications.
NASA says: ‘Recent observations and forecasts show that the (magnetic) region is expanding to the west and continues to weaken in intensity. It is also divided – recent data shows the valley of the anomaly as a region of minimum field strength, is split into two lobes, and poses additional challenges for satellite missions. “
NASA has been monitoring these changes across South America and the South Atlantic Ocean. Continuous attenuation can significantly knock on board computers; interested in the data collection of satellites passing through it, too. Moreover, if a satellite in low Earth orbit is hit by the high-energy parts, it could even lead to a short circuit and cause an event called a single-event insurgency like SEU.
Even the International Space Station also runs through the SAA and depends on the magnetic field for protection against the harmful radiation.
