Sky Hotspots: The Senders of Ultra-Particles Identified express

Original: "Rare Transients in Nearby Galaxies Explain Ultra-high-energy Cosmic Rays"
· Imre Bartos, Marek Kowalski
arXiv:2510.06193 · 2025-10-07 · CC BY 4.0 · 1 min
Neutron star mergers in nearby galaxies explain the clumps of cosmic rays in the sky.

📄 Showing the "Simple" version — "Popular" is not ready yet. Add it to favorites to help prioritize it.

Every day, particles with colossal energy enter Earth's atmosphere, like unsigned letters. Their source long remained a mystery. New research shows: these 'visitors' point to nearby galaxies, where from time to time catastrophes occur — collisions of neutron stars, ultra-dense spheres the size of a city but with the mass of the Sun. Upon impact, they scatter particles like postal items, and some fly straight to us.

Seven of the ten brightest nearby galaxies precisely coincide with hotspots in the sky where particles are especially abundant. The chance of such a coincidence happening randomly is less than one-tenth of a percent.

The same model explains why the northern and southern hemispheres see a slightly different 'assortment' of particles: simply, the nearest 'post offices'—the sources — are located on different sides of the sky. Previously, it was thought that the composition of rays depends only on energy, but now it's clear: the key to the puzzle lies in the arrangement of the sender galaxies.

One such particle, smaller than an atom, carries energy comparable to a baseball's impact, like a carrier pigeon delivering a truck.

Scientists
Bernhard RiemannJoseph WeberKarl SchwarzschildKip ThorneRainer WeissAlbert Einstein
Concepts
ultra high energy cosmic ray source cosmic rays ultra high energy gamma ray red galactic nuclei neutron star light emission exoplanets around red dwarfs early universe galaxies neutrino sources hot jupiter atmospheres starlight early universe star formation dust transparency anomaly bubble transit quasi periodic eruptions axion dark matter ultralight axion particle acceleration redshift transient