Radiation Has Effect on Mars Mission

NASA now has to expose astronauts to cancerous, or even lethal, levels of space radiation. It's an ethical quandary for those involved in NASA's renewed push toward deep-space exploration. And it's being explored by some of the most distinguished scholars, scientists, engineers, health professionals and ethicists in the nation.

On a 500-day round trip to Mars, astronauts would fly outside the Earth's magnetic field, which largely protects International Space Station crews and the planet from deadly forms of space radiation. Those flying beyond Earth orbit would face consequential radiation risks, including exposure to: Solar energetic particles generated by solar flares or coronal mass ejections from the sun. Galactic cosmic rays from the exploding stars, quasars and gamma ray burst outside our solar system. Shielding and sheltering measures can protect crews from solar energetic particles, but new breakthroughs in lightweight materials are needed to make deep-space missions possible.

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