For humans to explore deep space or live on other planets, we must learn how to deal with the effects of long-term exposure to potent space radiation, which can cause cancer and gene mutations, affecting subsequent generations. Lab mice are important tools for studying radiation effects, but currently, mice can’t go to the station. So instead, this investigation will send frozen mouse embryos for a ride in space and implant them into surrogate mothers on their return to Earth. Scientists will use these space mice to study longevity, cancer development, and gene mutations.