The technical term for this particle is "ultra-high-energy cosmic ray." The "ray" part is a misnomer as cosmic rays are actually particles of various sorts.
The ultra-high-energy cosmic ray got its nickname of "OMG" for two reasons. One, it travels at almost the speed of light, a speed that is considered fast for even a cosmic ray. Its sheer speed gives it the same kinetic energy as a fastball despite being a tiny particle. Two, when it inevitably hits a molecule nitrogen or oxygen, the particle explodes into a shower of secondary particles. The new particles are slower and have less energy, but there is a lot of them.
The first sighting took place in 1991. A cosmic ray detector at the University of Utah caught the spectacular arrival of the OMG particle.
Radio telescopes and other dedicated detectors have been trained on the skies since that day. However, only a hundred of the ultra-high-energy cosmic rays have been recorded. (Related: Understanding the breathtaking power of solar wind.)
Accelerating a charged particle to nearly the speed of light requires a huge amount of energy and a very powerful magnetic field that directs all of that power into a single particle. There are a number of events that can provide one or both of the requirements to create the OMG particle.
The first candidate is a supernova, a giant star that is going out with a bang. It has the prerequisite magnetic fields and plenty of energy. However, experts doubt that a mere exploding star can provide enough power for the process.
The second theory involves active galactic nuclei. At the heart of many galaxies are huge black holes. As matter careens towards the black hole, the material is squeezed and heated up into an accretion disk that has enough power and magnetic fields for the particle.
But most of these galaxies are too far away from Earth. Even if they can produce OMG particles that travel just slower than light, those particles would collide with so much cosmic microwave background energy that they will slow down to a halt long before they reach us.
One galactic nucleus is close enough to merit suspicion. Centaurus A is anywhere between 10 to 16 million light-years from the Milky Way. Several studies suggest that cosmic rays originate from its direction.
The problem is that the Milky Way generates its own magnetic field. This field changes the path taken by approaching cosmic rays, turning the straightforward fastballs into trickier curve balls. In order to figure out the original trajectory of a cosmic ray, you have to compensate for the effects of the Milky Way. Unfortunately, researchers are still mystified by our home galaxy's magnetic field.
Other candidates include the Seyfert galaxies. While weaker than Centaurus A, these active galactic nuclei are still pretty bright and powerful. They are also much closer.
Gamma-ray bursts from very distant galaxies are also considered potential sources of the OMG particle. They are the brightest sources of electromagnetic energy in the universe.
While researchers wrangle over the origin of the OMG particle, practical people may want to look for ways to amend the DNA damage caused by these cosmic rays. Foods with antioxidants seem to protect and repair damaged cells.
If you want to read more about cosmic rays, you can browse Cosmic.news.
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