This happens when the gamma ray photons created by the jets slam into the photons from the blue star. Together they have enough energy to generate matter. The collisions effectively absorb the gamma rays by converting them into matter.
"This is something that can only happen with gamma rays," said Thompson. No other light has enough energy to create matter, and therefore be absorbed in this way.
This gamma-ray eating process makes the brightness of the gamma rays from the jets vary in a regular pattern over the four-day orbits of the two bodies.
When, from our view on Earth, the compact companion is buried deep in the light of the large blue star or on the far side of that star, the gamma rays from the jets are gobbled up by the "fog" of light and the matter-making collisions around the big star.
But when the black hole is on the near side of the star to Earth, we are peering through less fog and can detect some of the gamma rays that escape from the system. This creates the lighthouse-like pulsing.
Because LS 5039 is the clearest case of this gamma-ray absorption, scientists hope it will serve as a small-scale model of the gamma ray signals from gigantic quasars.
The light-spinning, "Rumpelstiltskin" duo may manage an impressive feat, but quasars, which are gamma-ray emitting mega-black holes, with the mass of billions of stars at the centers of galaxies, are in another league, altogether.
