This could be the first time you have heard about a white hole (WH). Meanwhile, we have been hearing for quite some time about “black holes” (BH) as regions in outer space where nothing — not even light — could escape. Such cosmological entities, roughly represented by a singularity or point of infinite energy/mass/information density and an event horizon defining the “size” of the BH, are increasingly subjects of study. In addition, the possibility of detecting gravitational signatures as the ones detected two years ago, coming allegedly from the collision and merging of two black holes, have increased their interest even more. So, what about WH?