Dose and Depth Dose Measurements on the Sixth Gemini Flight, A Comparison with the Gemini-4 Radiation Measurements

Two tissue equivalent ionization chambers were flown behind 0.4 gram/sq. cm and 2.5 gram/sq. cm of shielding inside the Gemini-6 spacecraft. The instruments measured radiation from primary cosmic radiation and trapped Van Allen charged particles. The total cosmic radiation dose for the mission was 4.8 millirad. Dose rates as high as 73 millirad/hour were recorded in the earth's radiation belts behind the 0.4 gram/sq. cm shield. The heavily shielded sensor recorded a corresponding dose rate of only 42 millirad/hour in the radiation belt. The total radiation dose for the mission behind the lightly shielded sensor was 19 millirad, while for the heavy shield the dose was 12.6 millirad. Radiation surveys conducted on the fifth revolution of the mission indicated reductions in skin dose levels from 59 to 72 percent for various astronaut and spacecraft shielding locations. (Author)