To explore the unknown in deep space, millions of miles away from Earth, it’s crucial for spacecraft to have ample power. NASA’s radioisotope power systems (RPS) are a viable option for these missions and have been used for over 60 years, including for the agency’s Voyager spacecraft and Perseverance Mars rover. These nuclear batteries provide long-term electrical power for spacecraft and science instruments using heat produced by the natural radioactive decay of radioisotopes. Now, NASA is testing a new type of RPS heat source fuel that could become an additional option for future long-duration journeys to extreme environments.
Historically, the radioisotope plutonium-238 (plutonium oxide) has been NASA’s RPS heat source fuel of choice, but americium-241 has been a source of interest for the past two decades in Europe. In January, the Thermal Energy Conversion Branch at NASA’s Glenn Research Center in Cleveland and the University of Leicester, based in the United Kingdom, partnered through an agreement to put this new option to the test.
One method to generate electricity from radioisotope heat sources is the free-piston Stirling convertor. This is a heat engine that converts thermal energy into electrical energy. However, instead of a crankshaft to extract power, pistons float freely within the engine. It could operate for decades continuously without wear, as it does not have piston rings or rotating bearings that will eventually wear out. Thus, a Stirling convertor could generate more energy, allowing more time for exploration in deep space. Researchers from the University of Leicester — who have been leaders in the development of americium RPS and heater units for more than 15 years — and NASA worked to test the capabilities of a Stirling generator testbed powered by two electrically heated americium-241 heat source simulators.
“The concept started as just a design, and we took it all the way to the prototype level: something close to a flight version of the generator,” said Salvatore Oriti, mechanical engineer at Glenn. “The more impressive part is how quickly and inexpensively we got it done, only made possible by a great synergy between the NASA and University of Leicester teams. We were on the same wavelength and shared the same mindset.”
Salvatore Oriti, mechanical engineer in the Thermal Energy Conversion Branch at NASA’s Glenn Research Center in Cleveland, adjusts the Stirling testbed in preparation for testing at the center in January 2025.Credit: NASA/Jef JanisThe university provided the heat source simulators and generator housing. The heat source simulator is the exact size and shape of their real americium-241 heat source, but it uses embedded electric heaters to create an equivalent amount of heat to simulate the decay of americium fuel and therefore drive generator operation. The Stirling Research Lab at Glenn provided the test station, Stirling convertor hardware, and support equipment.
“A particular highlight of this (testbed) design is that it is capable of withstanding a failed Stirling convertor without a loss of electrical power,” said Hannah Sargeant, research fellow at the University of Leicester. “This feature was demonstrated successfully in the test campaign and highlights the robustness and reliability of an Americium-Radioisotope Stirling Generator for potential future spaceflight missions, including long-duration missions that could operate for many decades.”
The test proved the viability of an americium-fueled Stirling RPS, and performance and efficiency targets were successfully met. As for what’s next, the Glenn team is pursuing the next version of the testbed that will be lower mass, higher fidelity, and undergo further environmental testing.
“I was very pleased with how smoothly everything went,” Oriti said of the test results. “Usually in my experience, you don’t accomplish everything you set out to, but we did that and more. We plan to continue that level of success in the future.”
For more information on NASA’s RPS programs, visit: science.nasa.gov/rps
Explore More
2 min readGLOBE-Trotting Science Lands in Chesapeake with NASA eClips
On June 16-17, 2025, 50 students at Camp Young in Chesapeake, Virginia traded their usual…
Article 19 hours ago 6 min read5 Things to Know About Powerful New U.S.-India Satellite, NISAR
Article 21 hours ago 3 min readNASA-Derived Textiles are Touring France by Bike
Article 4 days agoHence then, the article about nasa tests new heat source fuel for deep space exploration was published today ( ) and is available on NASA ( Middle East ) The editorial team at PressBee has edited and verified it, and it may have been modified, fully republished, or quoted. You can read and follow the updates of this news or article from its original source.
Read More Details
Finally We wish PressBee provided you with enough information of ( NASA Tests New Heat Source Fuel for Deep Space Exploration )
Also on site :
- Supermarket timings for Boxing Day and New Year revealed for Asda, Tesco, Sainsbury’s, Aldi, Lidl and more
- Trump rants about Epstein in Christmas Day post claiming he dropped ties with sex offender ‘long before it became fashionable’
- IND vs SL Dream11 Prediction, Dream11 Playing XI, Today Match 3, India Women vs Sri Lanka Women T20I series 2025