Page 8 - 2021 High-Reliability, Harsh Environment Connectivity eBook

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What’s Good for GEO may not be Good for LEO
In space, solar radiation has enough energy to break apart oxygen molecules (O2) and create single particles of atomic oxygen, often referred to as ATOX. These particles are particularly abundant at altitudes ranging from 180– 650km and can erode and otherwise damage many materials, including most polymers and even some metals, such as silver. The lower the altitude, the higher the ATOX density and its effects. Multilayer insulation (MLI) blankets, solar panels, wires, and cables located on spacecraft exteriors are all susceptible to this threat, which can significantly limit the service life of these external components and, as such, the mission. Therefore, effective protection against atomic oxygen is a key challenge for the space industry.
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» LEO satellites are not the only ones exposed to ATOX. All satellites in low orbit, including missions in polar orbit (POL), highly elliptical orbit (HEO), and geostationary transfer orbit (GTO), are affected as well.
Solutions designed to protect wire and cable insulation and other organic materials from ATOX damage typically involve wrapping, coating, or insulating the wires in aluminum trays or conduits, or routing cables to areas that are protected from atomic oxygen. But these solutions add mass to these extremely weight-conscious systems and decrease flexibility, both of which can be avoided by instead specifying flexible, lightweight, and ATOX-resistant wire solutions.
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» Axon’ Cable’s proprietary, Radatox-insulated wires and cables are 10 times more resistant to ATOX and up to 40% lighter- weight than typical perfluoropolymers (e.g., FEP, PFA, and PTFE), 100 times more ATOX-resistant than and twice as flexible as similar-thickness polyimide tapes like Kapton, and resistant to more than 200Mrad of radiation.