NASA is working on a new metal alloy that shrinks when heated, which could help stabilize its next generation of space telescopes. The alloy, called “Alloy 30,” was tested by scientists in the Astrophysics Division and showed promising results.
In traditional metal construction, materials expand when heated, causing problems for space telescopes as their components warm up. This can affect the shape of mirrors, making it harder to conduct observations. To address this issue, NASA has developed materials that compensate for expansion, such as those used in the James Webb Space Telescope and Nancy Grace Roman Space Telescope.
However, these current materials are not sufficient for future space projects like the Habitable Worlds Observatory (HWO), which aims to detect exoplanets with unprecedented precision. The HWO will require a contrast ratio of one to one billion to observe the faint light from distant planets.
To achieve this level of precision, the HWO needs to be 1,000 times more stable than existing telescopes. This is where “Alloy 30” comes in. According to NASA, a 1-meter-long piece of this alloy will shrink 0.003 mm for every 1° C increase in temperature.
When paired with other materials that expand when heated, such as titanium alloy, Alloy 30 can help compensate for the expansion and contraction. This has been demonstrated through successful tests, where a test mirror mounted on struts made of both alloys performed as expected.
The potential benefits of “Alloy 30” extend beyond space telescopes. It has also been used to improve thermal switch performance and reduce the effects of temperature changes on joints and optics. As a result, scientists are exploring various applications for this innovative alloy.
Source: https://www.theregister.com/2025/07/02/nasa_negative_thermal_expansion_alloy_tests