Free Astronomy Magazine January-February 2020

JANUARY-FEBRUARY 2020 The analysis of the Sunburst Arc helps astronomers to add another piece to the puzzle — it seems that at least some photons can leave the galaxy through narrow channels in a gas rich neutral medium. This is the first observation of a long-theo- rised process. While this process is unlikely to be the main mechanism that led the Universe to become reionised, it may very well have pro- vided a decisive push. !