NASA scientists have developed a new device to monitor harmful radiation exposure, which may help keep astronauts safe during deep-space missions such as the manned mission to Mars. To be launched on the fifth re-supply mission undertaken by Orbital ATK — an American aerospace and defence manufacturer — to the International Space Station (ISS), the Fast Neutron Spectrometer is designed to detect and measure the energy of neutrons, which are known to be specifically harmful to humans. “While there are already advanced instruments to detect gamma rays produced by supernovas or black holes, X-rays and other charged particles, we needed a way to detect and measure neutron radiation to quantify the impact on human biology,” said Mr Mark Christl, from the NASA’s Marshall Space Flight Centre in the US. “Neutron detection techniques have not seen the same leap in technology advancement,” Christl added. Neutron radiation is created when the high-energy neutron particles from the sun and outside our solar system interact with other particles or matter, such as a spacecraft or a planetary surface. However, they are only viable for about 13 minutes before they decay into charged particles. The Fast Neutron Spectrometer is comprised of an aluminum housing with a plastic scintillator that slows down a neutron when it hits the device and re-emits the energy in the form of light. NASA astronaut Shane Kimbrough installed the device on the space station in December last year. Since then, it has been moved to different locations around the interior of the station. The device will monitor neutrons for six months, sending data for any neutron strikes to a laptop computer on the station. Even though the space station’s radiation environment is not considered “deep space,” the spectrometer is a new capability ready for validation in a space environment. “These radiation detectors may force missions to change mid-stream, but it will help keep our astronauts safe,” Christl said.