Humans in space    Space is a lot different than on Earth. For one thing there isn’t enough oxygen to breathe, there isn’t enough gravity to hold one in position and everything floats around. Weightlessness allows humans to do things that they would otherwise be unable to do on Earth like effortless somersaults and being able to lift things that would have otherwise been too heavy on Earth. However, when living in space, humans must take extra steps in order to be safe and to live hygienically. For one thing, there is no gravity to hold things down so when humans sleep, they are strapped into a sleeping bag, when eating; the food is rendered sticky and is pre-packaged into airtight containers so they do not float around and affect the crew. Liquids would not stay in cups so drinks come in plastic packets with straws. When a crew member needs to shave or go to the toilet, he/she must turn on the vacuum to suck out the loose pieces so they do not float around. On early space missions, humans used to wear nappy like underwear or used waste bags to dispose of waste products. On the Mir space station the waste fluids from the toilet used to be recycled into drinking water. Because moving around in space is a lot easier than moving around on Earth, astronauts and cosmonaut’s muscles degenerate due to lack of exercise and use, so humans must exercise daily. The record time for living in space goes to the Russian doctor Valeri Poliakov who spent 438 days on the Mir space station. In order to venture out of the spacecraft and into space where there is total vacuum and no air, astronauts and cosmonauts must wear spacesuits which contain air pressure, oxygen, power, cooling, protection sometimes even backpacks which propels them along. Without the spacesuit, our blood would boil and our lungs would empty, dying in seconds. Earth’s atmosphere protects humans against harmful radiation emitted by the sun, though if one were to go to space, then one would be vulnerable to such dangers. Radiation accumulated by the body after a short spaceflight would be equivalent to having one X-ray scan, though astronauts and cosmonauts who are exposed to radiation over prolonged periods of time, like living in space stations, receive many times these doses which may then prove to be quite harmful to the body. Due to this risk, space missions are often planned so they do not coincide with solar flares as these emit harmful amounts of gamma radiation.