Radiation exposure and mission strategies for interplanetary manned missions

Cosmic radiation is an important problem for human interplanetary missions. The ‘‘Radiation Exposure and Mission Strategies for Interplanetary Manned Missions–REMSIM’’ study is summarised here. They are related to current strategies and countermeasures to ensure the protection of astronauts from radiation during interplanetary missions, with specific reference to: radiation environment and its variability; radiation effects on the crew; transfer trajectories and associated fluences; vehicle and surface habitat concepts; passive and active shielding concepts; space weather monitoring and warning systems

Accelerator-Based Tests of Shielding Effectiveness of Different Materials and Multilayers using High-Energy Light and Heavy Ions

The roadmap for space exploration foresees longer journeys and further excursions outside low-Earth orbit as well as the establishment of permanent outposts on other celestial bodies, such as the Moon or Mars. The design of spacecrafts and habitats depends heavily on the mission scenario and must consider the radiation protection properties of the structural components as well as dedicated shielding. In fact, short- and long-term effects caused by exposure to cosmic radiation are now considered among the main health risks of space travel. One of the current strategies is to find multifunctional materials that combine excellent mechanical properties with a high shielding effectiveness to minimize the overall load. In this work, the shielding effectiveness of a wide variety of single and multilayer materials of interest for different mission scenarios has been characterized. In the experimental campaign, reference and innovative materials, as well as simulants of Moon and Mars in situ resources, were irradiated with 1,000 MeV/u 4He, 430 MeV/u 12C and 962-972 MeV/u 56Fe. The results are presented in terms of Bragg curves and dose reduction per unit area density. To isolate the shielding effectiveness only due to nuclear fragmentation, a correction for the energy loss in the material is also considered. These findings indicate that the best shield is lithium hydride, which performs even better than polyethylene. However, the technical feasibility of shielding needs to be investigated. The classification of all materials in terms of shielding effectiveness is not influenced by the ion species, but the value changes dramatically depending on the beam energy. The output of this investigation represents a useful database for benchmarking Monte Carlo and deterministic transport codes used for space radiation transport calculations. These findings also contribute to recommendations for optimizing the design of space vessels and habitats in different radiation environments

Preliminary results from the LAZIO-Sirad experiment on board of the International Space Station

The experiment LAZIO-Sirad was placed on board the International Space Station (ISS) with a Progress cargo on the beginning of March 2005. It represents the continuation of previous experiments (also on board Mir station) with the Sileye devices. It was operational as part of the ”Eneide” mission for 10 days from April the 17th 2005. The experiment aimed to study and correlate measurements of cosmic ray and magnetic environment on board the ISS with two devices: the LAZIO detector, built for the mission and the Sileye-3/Alteino telescope fitted with special multimaterial shielding tile