Predicting radiation risk

European scientists have developed software for predicting the doses of radiation that astronauts will receive aboard the orbiting European laboratory module Columbus, which was recently attached to the International Space Station (ISS).

The new software accurately simulates the physics of radiation particles passing through spacecraft walls and then through a human body.

To predict the radiation risk faced by astronauts, engineers must tackle three separate problems: how much radiation is hitting the space vehicle, how much of that radiation is blocked by the available shielding, and what are the biological effects of the radiation on the astronauts?

The new software, funded by the Eurpean Space Agency (ESA)’s General Studies Programme and the Swedish National Space Board, concentrates on the second of those questions.

The software simulation itself - dubbed Dose Estimation by Simulation of the International Space Station (ISS) Radiation Environment (DESIRE) - was developed by Tore Ersmark of the Royal Institute of Technology (KTH), Stockholm, Sweden.

To build the program so that it could accurately simulate the physics of radiation passing into a spacecraft and then through a human body, he made use of a software toolkit known as Geant4, which simulates the propagation of radiation particles. But he also had to build a complete computer model of the International Space Station too. The characteristics of the space station, as well as its orientation, are crucial parameters in defining the amount of radiation that passed through it.

The Columbus module, launched into space by NASA's Space Shuttle on February 7, is equipped with radiation monitors to test out DESIRE's predictions. 'We are really pleased with the results from DESIRE and look forward to comparing them to the actual measurements,' said Petteri Nieminen, an ESA Technical Officer.