Pew Pew Pew!
Of much interest, and only two years ago:
Only recently, with the discovery of a cosmic ray “hotspot” in the sky, the detection of related high-energy cosmic particles, and a better understanding of physics at more familiar energies, have researchers secured the first footholds in the quest to understand ultrahigh-energy cosmic rays. “We’re learning things very rapidly,” said Tim Linden, a theoretical astrophysicist at the University of Chicago.
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Thomson has his money on threads of galaxies and dark matter called “filaments” that are draped throughout the cosmos and which, at hundreds of millions of light-years long, are among the largest structures in existence. There’s a filament in the direction of the hotspot. “It’s probably something in the filament,” Thomson said. In any case, he added, “we have an idea now of interesting places to look. And all we need to do is collect more data.”