radiation from space
...that no viable solution has yet been found to counteract radiation from space, which is a serious threat to astronauts on any future mission to Mars?
...that no viable solution has yet been found to counteract <b id="mwnQ"><a href="./Health_threat_from_cosmic_rays" id="mwng" rel="mw:WikiLink" title="Health threat from cosmic rays">radiation from space</a></b>, which is a serious threat to <a class="mw-redirect" href="./Astronauts" id="mwnw" rel="mw:WikiLink" title="Astronauts">astronauts</a> on any future <a class="mw-redirect" href="./Manned_mission_to_Mars" id="mwoA" rel="mw:WikiLink" title="Manned mission to Mars">mission to Mars</a>?