ENTER THE COSMIC BATTLEFIELD VIOLENT UNIVERSE
As ultraviolet radiation cascades down from space, Earth’s place as a life-friendly planet is under threat. The surface of our world is bathed in this high-energy radiation, and it penetrates our oceans to depths of 75 metres (246 feet). The damage is catastrophic. The intense glare fries ocean plankton, and those organisms which survive divert all their energy to repairing their DNA rather than photosynthesising. Oxygen levels then drop as carbon dioxide levels rise. The knockout blow for many larger species comes as dwindling plankton numbers offer scant food resources, with the effect rocketing up the food chain.
Thankfully this fictional future is very unlikely, but what would have caused such devastation? The answer is a gamma-ray burst (GRB). They often emit as much energy in a few seconds as our entire galaxy does in a year. If such a volley of gamma rays were to strike our
