Welcome | History | Science | Spacecraft | People | References | Multimedia | Home | Search | Tours | Site Map
One of the benefits of the Shuttle-Mir Program is the experience gained from working in a microgravity environment. This Shuttle-Mir web site offers many interesting insights and stories, including astronauts' comments on microgravity and the results of several science investigations in the fields of life sciences, medicine and manufacture.
Gravity is everywhere, but it is not felt in an orbiting spacecraft, where the sensation is more like that felt in an aircraft during a "free fall." Objects and people appear to be floating, although they still possess the same mass, which is evident in their inertia. This situation can be compared to a large boat floating near a dock; a person can easily move the boat, while still feeling its inertia, or "heft."
Living and working in microgravity presents pleasures and problems. Outside a spacecraft, astronauts performing EVAs (spacewalks) can move large objects, such as the Hubble Space Telescope, but they must use devices such as foot restraints and tethers to keep themselves from floating away while they work. Inside a spacecraft, astronauts "float about" freely and can use more of the craft's volume and can sleep as though "on a cloud." However, many astronauts develop short-term "space sickness." Also, tools can float away and simple activities such as eating require special techniques. Furthermore, prolonged exposure to microgravity causes changes in the human body, including bone loss and muscle atrophy and changes in blood and fluids circulation. These can partly be countered by strenuous exercising while in orbit.
Thagard on Space Sickness
Thagard on Returning to Gravity
Thagard on "Washing up"
Linenger Letter: "Don't spit your toothpaste into your towel"
Linenger Letter: "Propulsion and suction"
Linenger Letter: "Like being in a rowboat"
Wolf: Letter Home from Mir
Thomas on Microgravity
Dunbar on Microgravity
Life on Mir
Continue Long Tour
Tours | Timeline | Shuttle-Mir Background | Shuttle Flights & Mir Increments | Mir Expeditions
Graphic version available
page is best viewed with Microsoft Internet Explorer 4.0 or higher or Netscape
4.0 or higher.
Other viewing suggestions.
NASA Web Policy
Responsible NASA Official: John Ira Petty