This agreement between NASA and DARPA does align with the Moon to Mars Planning objectives, which aim at developing a blueprint for sustained human presence and exploration throughout the solar system. The collaboration between both entities encompass the development and demonstration of “advanced nuclear thermal propulsion technology as soon as 2027”, as specified by NASA Administrator Bill Nelson.
“Expanding our partnership to nuclear propulsion will help drive forward NASA’s goal to send humans to Mars.” – Pam Melroy, Deputy Administrator (NASA)
NASA explains further that using a nuclear thermal rocket enables a faster transit time, and this considerably reduces risks for astronauts. Besides, it appears essential to build more efficient transportation technology, as it could optimize a mission duration; this way, trips would require less supplies. And nuclear thermal rockets do respond to this challenge, as they “can be three or more times more efficient than conventional chemical propulsion”.
In such rockets, a fission reactor is used to generate extremely high temperatures; and then, the engine collects this heat and transfers it to a liquid propellant. After this, the latter is expanded and exhausted through a nozzle to propel the spacecraft. It is to note that nuclear thermal rocket engine tests were conducted more than 50 years ago, so NASA counts on leveraging their expertise gained from previous similar projects – as mentioned by Jim Reuter, associate administrator for NASA’s Space Technology Mission Directorate (STMD).
Although the results of this collaboration sound promising, this technology could be jeopardized if the engine proves hazardous – notably for the environment. In spite of these potential challenges, NASA and DARPA have high hopes of disclosing the first in-space demonstration as early as 2027.