Space is an inhospitable place, not only for humans but for satellites too. Within the next 5 years, many thousands of them will start circling the Earth. Once deployed, they will be subject to the vacuum of space, as well as extreme temperature swings. Such environments will ordinarily destroy electronic components/systems. However, these expensive pieces of hardware – which are becoming increasingly complex – are expected to last for anywhere up to 15 years. Materials that allow devices to become smaller, lighter and more durable are being asked to meet rising challenges.

Low-Earth-orbit (LEO) satellites travel through intense sunlight into the planet’s deep, cold shadow up to 16x/day, moving through temperatures from -170°C to +120°C every 90mins. This relentless cycle of acute heating/cooling can affect every constituent element – from circuit boards and battery systems to solar cells and structural composites. In addition to mechanical stresses from thermal cycling and decomposition caused by UV rays, vacuum exposure prompts outgassing, where materials release trapped gases which can potentially contaminate sensitive optics and sensors. Designing thermal management systems to withstand these rigorous environmental conditions is paramount.

Satellite designers are not only concerned about exposure to thermal cycling and vacuum conditions, but also with minimising weight and size. Every g and mm counts. To lower the cost of getting them into orbit, satellites are tightly folded to occupy as little launch rocket payload room as possible. Any thermal protection system (TPS) must survive the mechanical strain of tight packing, unfolding and deployment. These space restrictions can be extremely challenging. For example, one of Blueshift’s satellite customers recently found its design only allowed 200µm of space (roughly 2x the thickness of a human hair) for thermal protection material to be fitted inside the satellite. Traditional multi-layer insulation (MLI) blankets, used as the aerospace industry standard for decades, were simply too thick.

Due to temperature cycling, satellite components suffer continuous expansion and contraction once in space. The different materials found within batteries, solar cells and suchlike will expand/contract at various rates, causing stress and fatigue to surrounding structures. Dielectric and conductive layers of PCBs can warp or delaminate. Heated circuit lines can change shape, leading to distortions and signal failures. Extreme temperatures may also affect chemical reactions in batteries, causing their faster degradation, or reducing the strength and stiffness of polymers and soldering. Conversely, cold can cause plastics and other materials to become brittle and shrink, leading to cracking. Constant temperature cycling may also lead to condensation – especially in manned spacecraft, like the International Space Station (ISS), resulting in corrosion and electrical shorts.

High temperatures combined with the vacuum of space also present another problem – outgassing. Coatings, polymers, or adhesives often trap moisture or solvents during manufacture, with metals and glass naturally absorbing water from the atmosphere. At high temperatures and under vacuum conditions, the gases are released. Outgassing fogs sensitive optical lenses, solar panels and sensors. It also degrades sensor performance and interferes with critical measurements – proving particularly problematic for Earth observation satellites, communication systems and scientific instruments where optical clarity is crucial. Outgassing also causes materials to degrade over time and can even create unwanted thrust that affects orbital positioning. Consequently, NASA has defined a stringent outgassing standard (ASTM E595) restricting gas release from materials to <1.0% total mass loss and 0.10% condensable material under high vacuum and elevated temperatures.

As satellites become increasingly sophisticated, driven by higher power demands, complex payloads, plus next-generation solar and battery systems, the need for high-performance thermal protection has never been greater. It is not just about making satellites smaller or lighter, but about enabling more power-dense and capable designs without compromising on reliability. Thermal protection must go beyond simple insulation, delivering active, high-efficiency control that safeguards critical components from orbital temperature swings. Advanced TPS solutions are now available that address these demands. Blueshift’s AeroZero technology provides effective thermal protection across temperatures spanning from -200°C to +2,400°C. It can also protect structural composites from damage due to thermal stress and fatigue.

AeroZero thermal protection tapes are ultra-thin (<200µm) – meaning satellite designers can apply them on top of batteries and PCB sections to help reduce dramatic temperature swings. With densities as low as 0.38g/cm³ and accentuated flexibility, these tapes can conform to the complicated geometries and tight configurations found in satellites’ battery cells and electronics hardware. They are lightweight, helping to reduce launch costs, with their ‘peel-and-stick’ application streamlining manufacturing processes, plus reducing assembly time and labour costs.

A significant advance in satellite thermal protection comes from Blueshift’s AeroZero low-outgassing thermal tapes, which outperform traditional polyimide films, especially in the vacuum of space. Whereas polyimide films have long been valued for dielectric insulation and dimensional stability, AeroZero provides over 15× lower thermal conductivity and 8× lower thermal diffusivity in high vacuum (<10?5Torr) situations. This dual-function performance enables protection at both structural and system levels. Externally, AeroZero serves as a lightweight, radiation-tolerant barrier that shields carbon fibre and composite satellite structures. Internally, it acts as an efficient thermal break – minimising heat conduction into sensitive electronics during the hot side of orbit and preserving internal warmth on the cold side. ASTM E595 compliant, it also ensures that no volatile materials are released which could compromise optics, sensors, or other precision instruments.

Used extensively in orbiting hardware, the latest thermal protection products are showing how modern material science is addressing thermal protection challenges in the ever-tighter confines of satellite design, while also meeting stringent outgassing standards. The future of satellite technology depends not just on innovative electronics, but on critical materials that protect systems from the brutal realities of space deployment.

Author: Tim Burbey

Check out the article here: https://www.epdtonthenet.net/article/218555/Staying-Cool-How-Satellites-Survive-the-Temperature-Extremes-of-Space.aspx