Positrons—the antimatter counterpart of electrons—are created in high-energy cosmic processes. When normal matter meets its antimatter counterpart, they annihilate, or vanish, and produce a distinctive 511 keV gamma-ray signal. Scientists use this signal to detect where these annihilations occur.

Source: [Phys.org](https://phys.org/news/2026-07-extragalactic-positron-annihilation-hotspots-milky.html)

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