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In the Cygnus X-3 system, record-breaking photons aren't born from direct light, but from helium nuclei colliding with the star's radiation and wind — and we see the glow of its shadow.
In the binary system Cygnus X-3, right here in our Galaxy, a black hole and a giant star whirl so tightly together that the star loses matter: it's swept away by a powerful wind. Jets blast out from near the black hole; recently, a telescope caught photons from them, each carrying the energy of a flying mosquito.
Here’s how they’re born: helium nuclei get accelerated in the jet, then fly outward and crash into the light and particles of the stellar wind. These collisions spawn particles that instantly transform into photons of record-shattering energy.
But the biggest surprise is that the light comes from a side where we shouldn’t see anything. Our line of sight lies almost in the orbital plane, and the jet pointed away ends up hidden behind a dense curtain of matter. Its photons push through longer, colliding more often, and in the end, the system’s shadow shines brighter than its direct light.