Earth’s magnetic field It not only serves to guide us with a compass, but it is one of the characteristics of the planet that contribute to our existence here.
A special house
Our planet is undoubtedly special, and it is not only that human beings have a clear preference for our home, but objectively it is, as far as we know, the only planet that harbors life. Many types of it.
Life exists here by a sum of favorable events: that the Sun is the right size, that we are at the right distance from it so that liquid water can exist, that a atmosphere with oxygen. And may the Earth have a magnetic field.
Although the Sun is one of those responsible for the flourishing of life on Earth, it could also be the cause of its end.
Because not only does it send us its light and heat, but also solar wind made up of high-energy particles and radiation, which are very harmful to life, and even to other features of the planet, such as the atmosphere.
Another one of the lucky coincidences of this planet we live on is that its core is made up of magnetic materials: iron and nickel.
Greenish-blue magnetic planet
Turns out that the earth is like a giant magnet, with a north pole and a south pole, which more or less coincide with the geographic north and south, but which can also move a little from time to time.
This is because the metals that make up the nucleus are in a liquid state, which favors a dynamic magnetic field.
This magnetic field extends around the planet, forming our magnetosphere, which is what stops the solar winds: the Aurora borealis they are the result of the interaction of the Sun’s charged particles with it.
Small variations in the magnetic field are normalBut larger variations are not uncommon, even a total reversal of the magnetic poles can happen: the north becomes the south and vice versa.
Do not panic
A group of scientists concluded that about 42,000 years ago there was a reversal event of the magnetic poles, which was evident in the rings of an ancient tree in New Zealand.
Magnetic field reversals leave Earth vulnerable for a time to cosmic rays from solar winds, which favor the formation of radioactive isotopes.
That New Zealand tree that was studied has a lot of Carbon-14, a radioactive isotope of carbon, which can be found in small amounts in organic matter, but in this case could only be explained by a event that would have let through an enormous amount of cosmic rays.
This may have caused the atmosphere to weaken for a time.: solar winds « sweep » the atmospheres, as we suppose it happened at some point on Mars, when it ran out of magnetic field.
So this that the group of researchers has called « Adams transition geomagnetic event », in honor of the science fiction author Douglas Adams, left the Earth without an ozone layer at least, causing climatic disasters and species extinction.
But do not panic, although that could happen again, maybe thousands of years before it happens. Or who knows, maybe it will happen on Thursday.