curiousauruses t1_j6isdwg wrote on January 30, 2023 at 5:10 PM

Reply to comment by Creepy_Toe2680 in NASA tested new propulsion tech that could unlock new deep space travel possibilities by Creepy_Toe2680

Does this mean the scify art where spaceships emit little rings from their exhaust isn't that far off?

a10t2 t1_j6jvqt1 wrote on January 30, 2023 at 9:13 PM

The "blue glow" type of propulsion is probably an ion engine, which is essentially just propellant + electricity. From a sci-fi perspective you'd want to generate that electricity with a fusion reactor.

Hampamatta t1_j6lthgq wrote on January 31, 2023 at 5:58 AM

Theoretically ion engines are the pinnacle of propulsion. Far more efficient than normal combustion engines. And doesn't satellites already use small ion engines for realignment?

Earthfall10 t1_j6lv6wv wrote on January 31, 2023 at 6:18 AM

Eh, there are other electric engine options that are better than ion engines, such as plasma engines or mass drivers. And if power isn't a limiting factor the ultimate in propellent efficiency is a photon rocket, aka a light bulb. No need to carry propellent, though you need 300 megawatts of photons to get a pathetic newton of thrust, so whatever reactor is powering it will need a shit ton of fuel. Though if you're using a laser array to push a mirrored sail that power plant can remain on the ground.

FrozenChocoProduce t1_j6mb7oo wrote on January 31, 2023 at 9:53 AM

I remember reading about a fusion reactor variant, that, while not ouputting a net gain, might be used (while using up porpellant) to accelerate particles in a rocket engine (usable only in the vacuum of space)...and some well-funded startup already developing this?