A new technology has been developed by researchers that could bring about a great change for a satellite or spacecraft. Meta-OSRs (Metamaterial optical solar reflectors) are the primary surface coatings on a spacecraft. It is designed to efficiently radiate heat away while reflecting away most of the solar optical spectrum.
OSRs are generally made of quartz tiles combined with thermo-optical properties which have the ability to withstand the harsh environment of space. For any spacecraft or satellite, the OSRs plays an important role in the thermal control of the system. OSRs which are glued to the external of the radiator panels are designed to get rid of solar radiation and dissipate the heat generated.
But the problem is that quartz tiles are fragile, heavy, and not apt for curved surfaces and has high costs to assemble and launch. Other options are based on polymer foils which suffer fast degradation and cannot be used for missions which last more than 3 to five years.
The researchers demonstrated that metal oxide is used to enable the latest meta-OSR coating, which will get patterned into the metamaterial with strong infrared emissivity and retain the solar spectrum’s low absorption. The technology of meta-OSR is completely based on space approved and durable inorganic coatings, that has the potential to be developed a great technology when applied to thin film type substances. The assembly and launch costs of OSRs is very high per square meter, so even a small weight reduction improvement can make a big change in the space industry.
The University of Southampton is also a member of the consortium of META-REFLECTOR, which also includes NIL Danish nanoimprint developer Technology, Thales Alenia Space, and CREO. The work of the consortium is Metasurface optical solar reflectors which use AZO transparent conducting oxides for radiative cooling of spacecraft and Smart Optical Solar Reflector which is VO2 Thermochromic Metamaterial-Based.
The team is currently focused on the upscale of the prototypes to more areas of the processes developed by the NIL technology. To preserve heat on the spacecraft during the startup and eclipses as well as to maintain the stability of temperature, having a passive control on the thermal emissivity is very important.
At the present stage, bulky mechanical parts are required for the thermal emissivity control. But these parts are very expensive and can cause failure fast. The new technology of meta-OSR will be a great change for the spacecraft and satellite industry.