ights have to supply oxygen, food, and water for their occupants and even longer flights need to have a way to dispose of or recycle waste. The even longer flights, spacecrafts will eventually need to become mostly self-sufficient. The astronauts will have to exercise and since the astronauts will be weightless, the shuttle will need to provide more than just the core physical needs for the astronauts to stay healthy.The weight of the craft is so important that it plays a crucial role in the amount of food supplied by the spacecraft. Most food provided to the astronauts is dehydrated, which is rehydrated by a device that is some what like a water gun, to save space as well as weight. However, some foods are given in their conventional form such as fruits, candy, and bread. Water is usually provided by fuel cells that also provide electricity to the whole ship. The reaction between Hydrogen and oxygen provides the electricity and creates water as well. A small amount of water is also carried onboard in case of emergencies. Water is also recycled on long duration missions aboard space stations. In this process, drinkable water is extracted from a combination of waste water, urine, and moister from the atmosphere in the cabin. This system will be recycled was used on the MIR space station and is planned to be used on the International Space Station.Skylab, the first US space station, was the fist to offer its crew a chance to bathe in space by installing a collapsible shower. To prevent water from escaping and floating around the cabin, the astronauts sealed the shower once inside. Astronauts had a hand-held nozzle to dispense water and then a vacuum to remove the water. On the space shuttle on Mir, where the showers malfunctioned, astronauts and cosmonauts have had to take sponge bathes in order to stay clean. On the International Space Station, showers will be provided in the habitual module.Most piloted spacecrafts carry...
