NASA invests in new nuclear rocket concept for the future of space exploration and astrophysics

Within the coming years, NASA plans to ship a number of astrobiology missions to Venus and Mars to seek for proof of extraterrestrial life. These will happen alongside crewed missions to the moon (for the primary time because the Apollo Period) and the primary crewed missions to Mars.

Past the interior solar system, there are formidable plans to ship robotic missions to Europa, Titan, and different “Ocean Worlds” that might host unique life. To perform these targets, NASA is investing in some attention-grabbing new applied sciences by way of the NASA Revolutionary Superior Ideas (NIAC) program.

This 12 months’s choice consists of solar-powered aircraft, bioreactors, lightsails, hibernation expertise, astrobiology experiments, and nuclear propulsion expertise. This features a idea for a Thin Film Isotope Nuclear Engine Rocket (TFINER), a proposal by senior technical workers member James Bickford and his colleagues on the Charles Stark Draper Laboratory—a Massachusetts-based impartial expertise developer.

This proposal depends on the decay of radioactive isotopes to generate propulsion and was lately chosen by the NIAC for Phase I development.

As their proposal paper signifies, superior propulsion is crucial to realizing a number of next-generation mission ideas. These embody sending a telescope to the focus of the sun’s gravitational lens and a rendezvous with a passing interstellar object. These mission ideas require fast velocities which are merely not attainable with standard rocketry.

Whereas lightsails are being investigated for rapid-transit missions inside the solar system and Proxima Centauri, they can not make the required propulsive maneuvers in deep space.

Nuclear ideas which are attainable with present expertise embody nuclear-thermal and nuclear-electric propulsion (NTP/NEP), which have the required thrust to succeed in places in deep space. Nonetheless, as Bickford and his staff famous, they’re additionally giant, heavy, and costly to fabricate.

“In distinction, we suggest a skinny movie nuclear isotope engine with ample functionality to go looking, rendezvous, after which return samples from distant and quickly transferring interstellar objects,” they write. “The identical expertise permits a gravitational lens telescope to be repointed so a single mission might observe quite a few high-value targets.”

The essential idea is much like a solar sail, besides that it depends on skinny sheets of a radioactive isotope that makes use of the momentum of its decay merchandise to generate thrust.

As they describe it, the baseline design incorporates sheets of the Thorium-228 measuring about ~10 micrometers (0.01 mm) thick. This naturally radioactive steel (usually utilized in radiation therapy) undergoes alpha decay with a half-life of 1.9 years. Thrust is produced by coating one aspect with a ~50-micrometer (0.05 mm) thick absorber layer, forcing alpha particles within the course reverse of journey.