A satellite sensor fails. A light-collecting panel is damaged. Usually, parts like these can’t be repaired from the ground, and a satellite can’t always be given a new job.
A 2009 U.S. document proposed a solution that sounds like science fiction: materials in a spacecraft that could change how they function in response to a software command. A faulty part might then be repurposed. The document also considered windows that could change how much light passes through them.
The document doesn’t describe technology already operating in space. It lays out an idea for the future and explores how software might affect the properties of physical materials.
A Command That Changes the Material
The document calls the concept “programmable matter”: material whose properties can change in response to a command. For example, a command might make it let through more or less light. The software doesn’t replace the material; it gives it an instruction that changes how it works.
The document describes smart materials, meaning materials that can change their properties. Under the proposal, software could give a spacecraft component a new function instead of having it physically repaired or replaced. A sensor, for instance, might adapt its operation to a new need.
From Adjustable Windows to Camouflage
A smart window is one of the simpler examples: it could change how much light passes through it. Other materials might help control heat or collect energy from different sources. The same component could therefore serve the spacecraft in different ways.
The document also ventures into active camouflage: changing a material’s appearance so it blends into its surroundings. It even raises the possibility of invisibility. These aren’t descriptions of a spacecraft that can already disappear, but futuristic applications the document envisions.
What Remains Unknown
It’s not known whether such materials can be made for spacecraft and operated reliably. The document cites obstacles such as radiation protection, heat control, preventing malfunctions, and guarding against malicious takeover. It presents the more advanced applications as long-term ideas, while treating smart windows and energy-saving materials as more realistic near-term possibilities.
