From a distance, supernovae explosions are fascinating. A star more massive than our Sun runs out of hydrogen and becomes unstable. Eventually, it explodes and releases so much energy it can outshine its host galaxy for months.
But space is vast and largely empty, and supernovae are relatively rare. And most planets don’t support life, so most supernovae probably explode without affecting living things.
But a new study shows how one type of supernova has a more extended reach than thought. And it could have consequences for planets like ours.
Earth has had a long and complex history since its formation roughly 4.5 billion years ago. Initially, it was a molten ball, but eventually, it cooled and became differentiated. The Moon formed from a collision between Earth and a protoplanet named Theia (probably), the oceans formed, and at some point in time, about 4 billion years ago, simple life appeared.
Those are the broad strokes, and scientists have worked hard to fill in a detailed timeline of Earth’s history. But there are a host of significant and poorly-understood periods in the timeline, lined up like targets for the scientific method. One of them concerns UV radiation and its effects on early life.
A new study probes the effects of UV radiation on Earth’s early life-forms and how it might have shaped our world.