U.S. and Russian hardware for the International Space Station will be carried in the SPACEHAB double module, a pressurized laboratory in the shuttle's cargo bay that is connected to the middeck area of the orbiter. Crew access is through a tunnel system located between the orbiter middeck and the SPACEHAB module.

Designed to augment the shuttle orbiter's middeck, the SPACEHAB double module has a total cargo capacity of up to 10,000 pounds and contains systems necessary to support astronauts, such as ventilation, lighting, and limited power.

Generally, two crew members are required for SPACEHAB operations. The SPACEHAB environmental control system is designed to nominally accommodate two crew members on a continuous basis. Additional crew members can be accommodated for brief periods at the expense of reduced cabin air heat rejection capability.


Microgravity Research Program

Working in partnership with the scientific community and commercial industry, NASA's Microgravity Research Program strives to increase understanding of the effects of gravity on biological, chemical, and physical systems.

Using both space flight- and ground-based experiments, researchers throughout the nation, as well as international partners, are working together to benefit economic, social, and industrial aspects of life for the United States and the entire Earth. U.S. universities, designated by NASA as commercial space centers, share these space advancements with U.S. industry to create new commercial products, applications, and processes.

Under the NASA Headquarters' Office of Life and Microgravity Sciences and Application, the Microgravity Research Program supports NASA's strategic plan in the Human Exploration and Development of Space Enterprise.

Microgravity research has been performed by NASA for more than 25 years. The term microgravity means a state of very little gravity. The prefix micro comes from the Greek word mikros ("small"). In metric terms, the prefix means one part in a million (0.000001).

Gravity dominates everything on Earth, from the way life has developed to the way materials interact. But aboard a spacecraft orbiting the Earth, the effects of gravity are barely felt. In this microgravity environment, scientists can conduct experiments that are all but impossible to perform on Earth. In this virtual absence of gravity as we know it, space flight gives scientists a unique opportunity to study the states of matter (solids, liquids, and gases) and the forces and processes that affect them.

Marshall Space Flight Center in Huntsville, Ala., is the lead center for NASA's Microgravity Research Program. The program manages Microgravity Science and Applications Project Offices at the Lewis Research Center in Cleveland, Ohio, and the Jet Propulsion Laboratory in Pasadena, Calif., and project offices at Marshall.

Under the project offices, the Microgravity Research Program is divided into nine major areas: five science disciplines, three research infrastructure programs, and the Space Products Development Office.

The science disciplines include biotechnology, fluid physics, materials science, combustion science and fundamental physics. The infrastructure activities include acceleration measurement, advanced technology, and the Glovebox Flight Program.

Marshall manages the Biotechnology Program and Material Science Program as well as the Glovebox Flight Program and the Space Products Development Office. Lewis Research Center manages the Fluid Physics, Combustion Science and Acceleration Measurement programs, while the Jet Propulsion Laboratory manages the Fundamental Physics and the Advanced Technology Development Program. As an element of the Biotechnology Program, Johnson Space Center manages bioreactor research in cell tissue growth.

In addition to the U.S. and Russian hardware for the International Space Station carried within the SPACEHAB module, additional unpressurized equipment for transfer to the space station will be carried on the new SPACEHAB integrated cargo carrier. The ICC, a cross-bay carrier that can accommodate 6,000 pounds of cargo, will be carrying a Russian cargo crane known as STRELA, the SPACEHAB Oceaneering Space System Box, and a U.S.-built crane called the orbital replacement unit transfer device.