Overview Box First Question: What do we already know about the subject? Radiation exposure can induce wide spectrum of diseases in radiation related approaches from earth to space. Radiation protection using different radioprotectors has many problems including acute toxicities and difficulties in their targeting to normal tissues. Second Question: What does your proposed theory add to the current knowledge available, and what benefits does it have? This hypothesis introduces gas producing microorganisms that might be able to improve radiotherapy outcome and also save astronauts in space missions. The biogases can act as antioxidants, anti-inflammation, anti-apoptosis agents. They also can decrease radiosensitivity. Third Question: Among numerous available studies, what special further study is proposed for testing the idea? Isolation microorganism in safe laboratory conditions in enough amounts, finding the best non-toxic dose of microorganisms, finding the best targeting techniques to deliver those microorganisms into normal tissues, genetically manipulations of microorganism to achieve the highest amount of biogases with lowest side effects can be done for testing the hypothesis.