An extremely lightweight fission rocket could reach the solar gravitational lens in 15 years

Novel propulsion concepts for shifting round space appear to be they seem to be a dime a dozen just lately. In addition to the standard argument between solar sails and chemical propulsion lies a possible third manner—a nuclear rocket engine. Whereas we have mentioned them right here at UT earlier than, NASA’s Institute of Superior Ideas has offered a grant to an organization referred to as Positron Dynamics for the event of a novel sort of nuclear fission fragment rocket engine (FFRE). It may strike the steadiness between the horsepower of chemical engines and the longevity of solar sails.

FFREs usually are not a brand new idea in themselves, however many have large technical hurdles to beat earlier than they are often thought of helpful. Their benefits, comparable to excessive particular impulse and intensely excessive energy density, are offset by their disadvantages, comparable to requiring an advanced type of plasma levitation.

Positron Dynamics hopes to tip that steadiness by using two separate breakthroughs derived from different areas of analysis. The primary novel strategy can be to place the fissile materials in an ultralight aerogel. The second can be implementing a superconducting magnet to include these fission particles.

FFREs basically make the most of the identical nuclear course of that powers energy-generating nuclear plants on Earth. Nonetheless, as an alternative of producing solely electrical energy, in addition they generate thrust and a really excessive quantity of thrust at that. Nonetheless, it isn’t sensible to ship a complete bar of uranium fuel, comparable to that utilized in fission reactors right here on Earth, up into space.

Embedding the gas itself into one of many lightest recognized human substances solves that drawback. Aerogels are terribly ethereal supplies that look ethereal when somebody is holding them, as they’re within the lead picture above. Embedding gas particles for the fission response in them can be a handy solution to maintain the gas collectively whereas nonetheless permitting the general construction to be mild sufficient to be lifted into orbit.

Nonetheless, the construction of the aerogels themselves would not do a lot to include the fission fragments are they break aside. To take action would require a large exterior drive, which is the place the superconducting magnet is available in.

Superconducting magnets are usually utilized in experimental fusion crops, the place they’re used to include the plasma wanted to warmth the fusion gas however which might in any other case destroy any regular materials. Given all of the curiosity in fusion analysis currently, high-power magnets have additionally been receiving further analysis consideration.

Including one to an FFRE would enable engineers to channel the fission fragments all in the identical path, successfully turning them right into a thrust vector. It has the added benefit of not permitting the fragments to destroy another elements of the engine as properly.

To date, that is all very theoretical, as there are nonetheless loads of hurdles to beat. However that’s precisely what NIAC is for—fund early-stage tasks and try and de-risk them. Possibly sometime FFREs will have the ability to hit that candy spot of pace and fuel efficiency that so many rocket scientists dream of.