Space radiation

Space travel is risky business, but not just during launch and re-entry

When we think of the dangers astronauts confront on a mission, we might think that the biggest threat they face would be being hit by a rogue space rock, running out of oxygen or maybe even colliding with space debris. In reality, one of the biggest dangers they face is a silent killer, quietly mutating and destroying their DNA during flight: radiation.

On Earth, we’re lucky: we sit under the atmosphere, which blocks cosmic rays and keeps us safe from most of the effects of radiation. But when a human leaves this blanket of protection, their body is vulnerable to being blasted by high-energy particles. Scientists don’t fully know the effects space radiation has on the human body, but we can learn a lot by using animal models and by studying astronauts during and after a mission.