Here I read NASA's articles on the five hazards of space flight and provide my layman's commentary along. These hazards include radiation, gravity fields, distance from earth, isolation, and hostile environments.

Radiation. The large and severe hazard of radiation. Ionizing radiation is zipping through space unabated and endlessly from the moment we leave the earth's protective atmosphere and magnetic field. It causes all kinds of harm to cells which cause deadly illnesses like cancer. Radiation shielding is an option, but one that is undeveloped and primitive currently. We are yet to build any space craft with radiation shielding adequate for long term space flight.

Gravity. Changing and weak gravity fields remain debilitating problems for astronauts. Too much, too little, or shifting gravity harm the human body. The more often and l ...