Before sending humans to space, we need to assess the potential radiation damage
The European Space Agency plans to evaluate cosmic ray damage to astronauts. As you may know, cosmic rays are beams of incredible energy, emitted during various events in space, such as a supernova, or meteorite crashing. These rays traverse space, and the heads of astronauts within space shuttles, without notable resistance. In order to protect our brave space explorers from a painful death, experiments have to be performed simulating the cosmic rays in space-like conditions. The only mechanism able to emit ion beams in Europe is UNILAG, owned by the GSI accelerator facility. Thus ESA have chosen it to perform their experiments.
So why exactly do we need this research? Well, here on Earth, the atmosphere protects us from rays and radiation, incoming from space. Astronauts, on the other hand, would be exposed to it constantly, while flying to the moon/mars or wherever they decide to. Radiation can damage human cells or cause genetic damage, which will manifest later as a tumor, or maybe even in the offspring. So the first colonizers reach Mars, establish a small outpost. Everything goes well, they have children... but wait! The children have various mutations, resulting in a colony filled with bloodthirsty laser-shooting mutants. I'm sorry, that was a bit off-topic, but there really is nothing more to this. The experiments are planned to begin later this year. Heh, who knows, maybe this will lead to an ion-cannon like in the Command & Conquer series. Some of the great inventions were made accidentally, like the EMP.