Original Date: 04/26/1999
Revision Date: 01/18/2007

Marshall Space Flight Center (MSFC) has developed and implemented orbital atomic oxygen simulation facilities based on the physical characteristics of a low earth orbit environment. This capability is used to determine the long term exposure characteristics of objects launched into space. Previously, no means existed for examining the interaction of materials with orbital atomic oxygen. In November 1982, the Center first began studying this area via the Evaluation of Oxygen Interaction with Materials (EOIM)-1 on STS-5. Subsequent studies include EOIM-2 (August 1983); EOIM-3 (August 1992); the STS-41G Atomic Oxygen Interaction Experiment (October 1994); and the Long Duration Exposure Facility (LDEF) (April 1984 to January 1990).

Orbital atomic oxygen simulation involves the generation of atomic oxygen. MSFC employs three methods for achieving this task: (1) thermal plasma ashers; (2) out-of-field atomic oxygen drift tube simulators; and (3) 5 eV neutral via the Atomic Oxygen Beam Facility. Each method generates atomic oxygen plasma on the surface of the material under test. The radiation within the plasma represents the spectral line of atomic oxygen. By measuring the magnitude of the spectral line intensity, MSFC can calculate a relative figure-of-merit that is proportional to the strength of interaction between the atomic oxygen and the test material. Each method has different strengths and weaknesses based on cost, safety, the atomic oxygen purity in the plasma, and the sample’s heating characteristics. MSFC’s current atomic testing activities involve materials qualification for anodized and alodine aluminum and nickel; kynar shrink tubing; aplix; super beta; labels; O-rings; slidewire; targets; teflon overcoats; pro seds; and the NASA Jet Propulsion Laboratory’s flight experiments. Future activities include continued support for International Space Station (ISS) and solar sails.

MSFC’s orbital atomic oxygen simulation facilities provide a robust means for simulating orbital atomic oxygen in a low earth environment. The Center performs this service for NASA missions as well as vendors and contractors. This unique capability enables the space industry to determine the long term exposure characteristics of objects launched into space.

For more information see the Point of Contact for this survey.