sheet number: FS-2001-07-136 -MSFC
The space environment - with its extreme levels of ultraviolet radiation, atomic oxygen, hard vacuum and contamination -- has a strong degrading effect on some types of materials. Qualifying materials for long-term use in space is made especially challenging because this unique environment is so difficult to simulate in a laboratory. With MISSE, no laboratory is needed. On-orbit testing is accomplished by flying the materials outside the International Space Station for a period of one to three years.
Samples for the MISSE experiment will be mounted to the Space Station during the STS-105 Space Shuttle Mission, ISS Mission 7A.1, in August 2001. They will be mounted by a Space Shuttle crew member during an Extravehicular Activity (EVA), commonly called a spacewalk. Backdropped by a sunrise, the newly installed Materials International Space Station Experiment (MISSE) is visible on the International Space Station. (NASA)
Samples will be contained in two Passive Experiment Containers (PECs). To fully expose the experiments to the elements, the crew will open each Passive Experiment Container after it is mounted to the Space Station. MISSE is a passive experiment, which means that aside from deployment and retrieval, no other interaction is involved. The specimens have no power, data, thermal or maintenance requirements. The two carriers will be retrieved approximately one year after deployment and returned to Earth on a later flight. After the MISSE samples are returned, scientists will analyze the materials to see how they fared.
MISSE is a reflight of two reusable Passive Experiment Containers flown on the Russian space station Mir in 1996 and 1997 as part of the Mir Environmental Effects Payload (MEEP). Like MISSE, this experiment studied the effects of the space environment on a variety of materials, some of which were intended for use on the International Space Station. Materials included paint samples, glass coatings, multi-layer insulation and metallic materials.
Space Shuttle crew members attached the samples to the exterior of Mir's docking module during the STS-76 mission in March 1996 while the Shuttle was docked with the Russian space station. The samples remained attached to Mir until September 1997, when the experiment was retrieved by the Space Shuttle crew on the STS-86 mission. After the samples were returned to Earth, scientists analyzed each material to determine how it fared when unprotected by Earth's atmosphere.
By examining how the materials fare in the harsh environment of space, researchers can gain new insight into improving materials for use in future space missions. The International Space Station is the ideal venue for such an experiment, because it tests the materials in the unique environment for which they are eventually destined.
Like many NASA experiments, MISSE also has the potential to improve products for consumers on Earth. One such product is exterior paint. Outside the Space Station, coating samples will be exposed to high doses of ultra-violet and other radiation from the Sun. On a more limited scale, this is similar to what painted - or coated -- surfaces are exposed to on Earth, thanks to Earth's atmosphere. By applying knowledge from the MISSE experiment, engineers can gain new insight into creating coatings on Earth that are less likely to degrade with time.
More information on MISSE and other Space Station experiments can be found at: