Engineers from the United States Naval Academy are developing a novel radiation monitoring system for astronauts of future missions to Moon, Mars, and (of course) beyond.
From the press release by the National Space Biomedical Research Institute:
The electronic output module held by Vincent L. Pisacane, Ph.D., collects information from sensors housed in various locations within the spacecraft. The microdosimeter will use the measurements to directly estimate radiation risk.
“Astronauts are exposed to radiations from different sources including particles trapped in the Earth’s magnetic field, cosmic rays and energetic solar events,” Pisacane said. “The instrument measures the integrated effect of a radiation field since damage depends on the types of radiation and their energy.”
Pisacane and his colleagues have developed two systems; one for ground-based lab testing and one for use in space. The microdosimeter flight instrument will be tested aboard the USNA student-built MidSTAR-1, a satellite developed by midshipmen expected to launch in early 2007 aboard a Lockheed Martin Atlas V launch vehicle. The goal of the project is to reduce the size of the sensors to the size of a deck of cards.
The flight instrument consists of three sensors and an electronic output module that collects and stores data for transmission to the ground. One sensor will be near the exterior of the spacecraft and the other two housed at different locations inside. Of the interior sensors, one resides in a block of polyethylene, which will simulate the effect of radiation on tissue.
“The sensors measure the deposition of radiation energy in tiny microscopic elements similar in size to a red blood cell,” Pisacane said.
Each of the three sensors provide an energy spectrum from the various locations within the spacecraft every three hours, but can provide more frequent updates if an enhanced-radiation event occurs. The microdosimeter will use the measurements to directly estimate the radiation risk. On the MidSTAR-1 test flight, the group will focus on testing the device’s sensitivity, resolution and response to noise.
“The microdosimeter can also be used to evaluate the effectiveness of shielding materials,” Pisacane said.
On Earth, the microdosimeter’s capabilities will be useful for nuclear material clean up, in detecting radioactive devices, and to monitor patients undergoing radiation treatment.