Detection of cosmic rays, all from a Galaxy which is pretty far away
The Pierre Auger Collaboration has definitely put an answer to the question of whether or not there are particles from outside the Milky Way Galaxy or not. The articles go by the name of – “Observation of a large-scale anisotropy in the arrival directions of cosmic rays above 8 + 1018 eV”, and according to some expert opinion, the study of the distribution of cosmic ray arrival will be the first step in the determination of where the extragalactic particles originate from.
The largest ever cosmic ray observatory was built, in order to help the scientists to collaborate and work together. The observatory stands tall in Pierre Auger, an observatory which, by the way, is found in Argentina. Included in this collaboration are David Nitz and Brian Fick, professors of physics at Michigan Technological University.
Karl Heinz Kampert, a professor who is present in the German University of Wuppertal, stated that : “We are now considerably closer to solving the mystery of where and how these extraordinary particles are created, a question of great interest to astrophysicists.” This also seemed to be the opinion of the spokesperson for the Auger Collaboration, a collaboration which involves more than 400 scientists, who come around all across the world, ranging from 18 countries.
So, why exactly does the study of Cosmic ray seem so important? Why exactly does the study of cosmic ray seem to be of that much interest? Well, for one – Cosmic rays are the nuclei of elements from hydrogen to iron. Studying them gives scientists a way to study matter from outside our solar system – and now, outside our galaxy. Cosmic rays help us understand the composition of galaxies and the processes that occur to accelerate the nuclei to nearly the speed of light. By studying cosmic rays, scientists may come to understand what mechanisms create the nuclei.
Further continuation can be taken from the fact that Carl Sagan, a famous Astronomer once stated – “The nitrogen in our DNA, the calcium in our teeth, the iron in our blood, the carbon in our apple pies were made in the interiors of collapsing stars. We are made of starstuff.”
In the most simple of terms, the study of cosmic rays can help us answer questions not only about the fundamental questions about our universe, but also questions about our galaxy, and indeed, ourselves.
So, exactly how are cosmic rays detected? Well, such rare particles are detectable because they create showers of electrons, photons and muons through successive interactions with the nuclei in the atmosphere. These showers spread out, sweeping through the atmosphere at the speed of light in a disc-like structure, like a giant dinner-plate, several kilometres in diameter. They contain more than 10 billion particles.