article_snippet: human missions to Mars, the U.S. space agency has revealed.
article_snippet: landing astronauts on Mars. '
article_snippet: The mission is seen as an important step towards eventually sending humans to Mars and returning humans safely. '
article_snippet: Nasa's ultimate goal is to send humans to Mars, and humans say The mission will be an important stepping stone towards getting there.
article_snippet: Astronauts returning home with samples from Mars will hold a treasure trove of research scientists will study to unlock new knowledge about Mars and the solar system's history.