Soil Heat Shield Concept Passes Arc Jet Testing
Arc jet testing under intense temperatures and pressures showed that heat shields made from the soil of other worlds will stand up to the conditions they would encounter plunging through Earth's atmosphere, researchers said this week.
Michael Hogue, a researcher at NASA's Kennedy Space Center in Florida, led a team of engineers as they exposed samples of heat shield materials to an intense plasma wind known as an arc jet at Ames research Center earlier this week. The 2-inch by 4-inch shaped blocks were made from different mixtures of soil simulating lunar and Martian regolith.
The scientists recorded no burn-through or uneven erosion of the surface on any of the samples through a series of progressively higher energy levels, Hogue said.
The test results mean the idea of making heat shields out of the soils, or regolith, of other planets and moons remains feasible, Hogue said.
For mission planners in the future, the concept could produce a windfall of weight savings because spacecraft could make their own shielding on planets and moons where gravity is so low that it would take little energy to lift even a massive heat shield from the surface into orbit. Lifting material from the Earth's surface and gravity well requires a great deal of thrust and cost, by contrast.
Applications could include an uncrewed spacecraft molding a heat shield on a Martian moon and then riding it through the Martian atmosphere to make a landing. The same principle could be applied to a large habitation module for astronauts or any number of similar missions.
The technology remains in its infancy, but with strong test results, Hogue and his team will be able to complete a report by the end of November and apply for continued funding to develop the innovation further.
› Read more about the regolith heat shield concept
NASA's John F. Kennedy Space Center