NASA device to keep astronauts safe from space radiation

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.
Launched on the fifth Orbital ATK resupply mission 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.
Understanding neutron radiation will help keep crews safe when NASA sends humans to Mars.
"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 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 said.
Neutron radiation is created when the high-energy particles from our Sun and outside our solar system interact with other particles or matter, such as a spacecraft or a planetary surface.

However, these neutrons 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 glass scintillator fibres that absorb neutrons and re-emit 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 and it currently resides in the Node 1 module.
The Fast Neutron Spectrometer will monitor for neutrons for six months, sending data for any neutron strikes to a laptop computer on the station. That data will be downloaded daily for processing and analysis.
The device was tested and calibrated at particle accelerators and by using other radioactive sources on Earth.
If the technique is verified, Christl hopes it can be used on future missions to determine when and how much neutrons are contributing to the radiation absorbed by a crew of space travelers.

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.
"We use different techniques for charged particles and neutrons and we'll need to know the dose from both to know how much radiation the astronauts are receiving," said Christl.
"These radiation detectors may force missions to change in mid-stream, but it will help keep our astronauts safe," he said.