Living Interplanetary Flight is an experiment that scientists do to find out if it's possible for people to travel and live in space for long periods of time. In this experiment, a spacecraft is sent into deep space with a crew of astronauts who will travel and live in the spacecraft for years at a time. During this time, the astronauts will be doing experiments to see how they will live in space, such as exercising and eating, and how they can stay healthy. At the end of the experiment, the astronauts will return to Earth and the scientists will be able to use the results to help with future projects and to help make space travel safer and easier for everyone.