2024-03-03 19:00:00
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Cosmic rays, high-energy particles that arrive from outer space, have been a complete bafflement for scientists since their discovery at the beginning of the 20th century.
These mysterious charged particles, composed mainly of protons and atomic nucleitravel at speeds close to the speed of light and constantly penetrate our atmosphere, entering it.
Despite their name, cosmic rays are not true “rays” in the most literal sense of the word, but rather groups of particles that, seen at high speeds in perspective, they can create a simile with trails that cross the Cosmos.
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WHAT ARE COSMIC RAYS AND WHERE DO THEY COME FROM?
Cosmic rays are, in this way, sets of charged subatomic particles that are move at extremely high speedsmostly covering a great variety and diversity of particles, with protons and atomic nuclei being the most common components.
These come from outer space, and move throughout the Universe, crossing long distances and all kinds of astrophysical phenomena, such as the gravitational attractions of stellar objects and their magnetic fields.
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According to their composition, they are divided into two main categories: primary and secondary rays. The primary rays will be those that reach Earth directly through the Earth’s atmosphere, while those secondary They originate from certain interactions between the primaries and the components of the Earth’s atmosphere.
Whatever they are, the energy of all of them is astonishing and, some of them, can have energies millions of times higher than those of the particles accelerated in particle colliders on Earth.
However, its origin remains somewhat uncertain. Although it is known that the Sun emits this type of rays during the large eruptionsthese events are rare, so they would not explain the constancy of the rays, even taking into account the eruptions of other stars similar to the Sun.
Therefore, they also include the supernovae as a probable source, at least, of the initial acceleration of many of the particles contained in the rays, since the remains of these explosions are powerful radio sources in which it is possible to observe high-energy electrons.
In 2007, Argentine scientists from the Pierre Auger Observatory made a discovery that helped further consolidate the origin of lightning.
They found evidence that most cosmic ray particles They came from the constellation Centaurus, which contained an active core galaxy with a black hole at its core. Through the rotation of the black hole, matter made up of protons was expelled, which, upon reaching the Earth, generated cascades of cosmic rays during the collision with the atmospheric layers.
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DETECTORS AND EXPERIMENTS
Thanks to the latest advances in detectors and experiments, there has been, in recent years, a great advance in research in this field. These sophisticated devices allow scientists to perform various precise measurements and analyze the composition of cosmic rays, better understanding their origin and behavior.
One of them is the so-called particle spectrograph, which allows us to better study the elements that make them up. These are devices that allow the energy, charge and direction of the particles to be measured, providing crucial information to understand their nature.
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MAGIC, a Cherenkov telescope in operation on the Canary island of La Palma. On foggy nights, you can see the lasers that focus the mirrors.
Another very common tool is the Cherenkov telescope, which focuses on measuring the Cherenkov radiation. This manifests as light that appears when charged particles, such as electrons, move through dielectric media at a speed greater than that reached by photons in that same medium.
They are very valuable telescopes for studying high-energy cosmic rays, such as those coming from highly energetic sourcessince they are the only ones capable of reaching those energies.
Lastly, and perhaps the most curious case, it is also common to perform certain experiments in stratospheric globesas they are the means that provide a platform to study them at altitudes higher than those reached by most aircraft, but without the costs associated with satellites.
Equipped with specialized energy or charge detectors, these balloons make it possible to collect crucial data to understand the variation in the characteristics of cosmic rays with altitude and, therefore, what happens when they penetrate the atmosphere.
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IMPACT ON EARTH AND LIFE
If you’re worried that these rays could reach you and hurt you, don’t worry: at ground level, most cosmic rays are absorbed by the atmospherewhich greatly reduces its direct impact on human health.
Now, it is true that in high-altitude flights, such as space flights or long-distance commercial flights, the exposure can be somewhat greater. However, the consequences are still not considerably dangerous for the health of either the astronauts or the crews.
On the other hand, these rays also play a crucial role in cloud formation in Earth’s atmosphere. Secondary particles generated by the interaction of primary cosmic rays with the usual components of the atmosphere can act as condensation nuclei for the formation of water droplets, thus contributing enormously to the formation of clouds.
This process, known as nucleation, can have implications for climate modulation, affecting the amount and type of clouds present in our atmosphere.
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