EMDrive finally put to rest

Why not just attach a submarine nuclear reactor to ion engines?

How fast could something like this go?

At 0.3g acceleration we could get to Mars under a week. 0.1g would be enough to revolutionise space travel.

S8G reactor is 2750 tons or 2494758 kg and produces 45MW
The best experimental ion engines deliver 5 newtons per 100kW
Assuming that scales correctly that would give you 2.25kN of thrust
So ignoring the weight of the engine(s) themselves and the huge amount of xenon you would need, still only leaves you with a .0001 TWR

That cone on the car backwards

1g acceleration is needed for interstellar travel

Why are people instantly aiming at interstellar?

In our minds we're already at Mars; now we want more.

i miss trollscience so much

In 1960, the editor of Astounding Science Fiction (then midway through changing it's name to ANALOG, which it still uses) became convinced the Dean Drive (a reactionless thruster, full of gears and spinning weights) actually worked.
He urged that one be fitted to a nuclear submarine and sent to Mars. The big balloon at the bottom is the radiator. All power plants need to reject waste heat and oceans are rare in Space.

It wasn't done because the Dean Drive doesn't work. But it's a very nice cover picture. Note that Mars still had canals & vegetation back then.

maybe you guys should listen to the current most important SCIENTIST (with Neil de Grease Tyson)
youtube.com/watch?v=Kr6qQybfwEg

>DUDE, TOPOLOGY LMAOO

What are the individual strands of the strings made of?

What show?

Which EM drive?
As far as i remember there were two EM drives withing the past few years that gained popularity, one that seemed kind of plausible and another that was just sci-fi fairy tales.

>At 0.3g acceleration we could get to Mars under a week. 0.1g would be enough to revolutionise space travel.
Is there a table of this information somewhere?

Smaller strings

200 videos on youtube about travel times in The Expanse.

Aren't chinks also working on a different type?

I thought the whole point was that it has no theoretical foundation

If experiment finds some effect though then maybe we'll see someone come up with a good explanation

The Emdrive (the copper cone looking thing) is the subject here. The Cannae drive has a different shape but "works" on the same principle. I think these are the fairy tales you're referring to. They exert force against quantum pixie dust.

The Woodward drive AKA Mach Effect Thruster at least has some theoretical underpinning. (Ernst Mach thought inertia was the result of the gravitational fields of distant matter. If there was no matter in the universe except the experimental set-up, there'd be no inertia. Einstein disagreed -- mostly. The issue hasn't been settled because removing all the matter in the universe is an impractical experiment. The Woodward drive supposedly reacts against that distant matter.)

The "inventor" has a theory. It's full of contradictions and no physicists agree with him. There are alternative "explanations" which will be trotted out IF and WHEN anything comes of it.

They're working on the Emdrive, the thing pictured in . They've claimed success -- then withdrawn it after finding errors in their methodology.
Unsubstantiated rumors that both the Chinese and the USAF are testing prototypes in orbit. The forces involved are so small that a zero-gee, vacuum environment far from anything else is the best place to check. In orbit, even small forces applied continuously will add up to easily measurable displacements.

Mars, at its absolute closest is about 0.59e8 km from Earth. Accelerate halfway at 0.3 gees (3 meters/sec^2.
0.59e11 meters = 0.5 * 3 * T^2
T = 198,000 seconds
Reverse the engine and begin slowing down. Braking takes the same time acceleration did.
T=396,000 seconds = 110 hours = 4.6 days
The internet can give you minimum, maximum, and average distances between any two bodies in the Solar system. Under continuous drive, trajectories are essentially straight lines and time varies as the inverse square root of the acceleration; i.e. to cut transit time in half requires quadrupling the boost.

Made a mistake! Mea Culpa!!!
Forgot to divide the distance to Mars by 2. That's the distance to turn-over.
Re-working the problem with more care, transit time at 0.3 gees varies from 4 days 11 minutes to 10 days 11 hours (plus a hair to avoid going too close to the Sun), depending on planetary positions.

>Earth to Mars in less than 2 weeks

God I fucking wish, anything that helps to shorten the distance between these distant worlds would help usher in a new unstoppable push for space travel, exploration and settlement, not to mention at speeds that quick, the moon is a 1 day trip away, the amount of humans living in space would skyrocket, we would have solid footing in interplanetary space... like going from sail to steam engines to cross the oceans, we would be able to cross the ocean of space in unimaginably short times.

Even if it takes several hundred years to leave our solar system, with technology that shortens space flight considerably we could open up the entire solar system to humanity, millions of people living in space, colonies, outposts and stations around every world, every moon, we just need that breakthrough.

>microwaves can't melt chocolate beems!

Ya'll just ignorant

Okay, EM drive max speds are quite low. If the data Im working off when last I looked into this is still correct controlled nuclear explosions are the only feasible way to reach another solar system.

You would want something very large, a complete civilisation in a cigar but it could take as little as 50yrs to reach our nearest neighbour star system. If we develop existing tech. Who knows what we could learn in close proximity to a binary star system and a red dwarf...

Something like that would want to be launched from near the heliopause though... This is hugely offtopic though and I dont want to derail here.

I just dont know much about the topic here except that it was proposed around a decade or two ago, the guy said he was shut down by the government but the device was low thrust and only for maneuvering satellites...

Err ion not EM muhbad but em is also low thrust.