Microquasars emerge as the Milky Way’s most extreme particle engines

LHAASO has uncovered that micro-quasars, black holes feeding on companion stars, are powerful PeV particle accelerators. Their jets produce ultra-high-energy gamma rays and protons that exceed long-held expectations. Precise cosmic-ray measurements reveal a new high-energy component, suggesting multiple sources within the Milky Way. These findings finally tie the “knee” structure to black hole jet systems.