Weightlessness and the human body.

Ignition: If we are ever to venture beyond Earth orbit and visit, perhaps even colonize planets and the moon, we must know the risk that our space explorers face. As we leave the Earth's surface and escape its gravitational pull, our bodies rapidly adjust to the new weightless environment. Many of the changes seen are similar to the process of Earth-based diseases i.e. anemia, osteoporosis, muscular atrophy, and immune system dysfunction -but in space these changes occur much faster than on Earth. Although we have observed and documented these changes, we have not yet answered these questions: