PLASMA MAGNET SAILS

[Anonymous No.11801868]

We need to discuss plasma magnet sails right now. Why the FUCK isn't this talked about.
Watch this video
https://youtu.be/0vVOtrAnIxM
Read this article
https://www.centauri-dreams.org/2017/12/29/the-plasma-magnet-drive-a-simple-cheap-drive-for-the-solar-system-and-beyond/
>no new meme tech like fusion or antimatter or exotic matter needed
>act like a reactionless drive because you don't have to carry reaction mass, infinite ISP
>just need electricity to create magnetic fields kilometers wide to act as sails for solar wind
>0.5 G constant acceleration
>further away from the sun, the bigger the field so thrust is constant
>get to Mars in ONE WEEK
>using sun as gravitational lens telescope possible
>0.2c and therefore Alpha Centauri possible
>able to use the solar wind of stars as you're approaching to brake
>downside is you can only go away from the sun, but you can build particle beams that can let you decelerate or send you back towards the sun
>Neptune's magnetic field strong enough for breaking on a direct trajectory
>nasa already tested a small scale prototype and it worked
>must be deployed outside earth's magnetosphere
Is this technology legit? Why hasn't there been much discussion or funding? This is almost as good as an expanse tier torch drive why aren't we building it now? I don't want to be cucked to just one star system

[Anonymous No.11801929]

>Is this technology legit? Why hasn't there been much discussion or funding?
because people don't know about it

[Anonymous No.11801951]

Fancy propulsion is usually promising but often either does not consider the mass impact of the power supply or outright assumes it will be massless.

What kind of power does that need, and what will be the power source's mass and its bulkier brother the cooling system impact on the efficiency of the propulsion?

[Anonymous No.11801956]

>>11801929
Why is such a promising technology so under the radar? I've heard so much about Alcubierre drive (impossible as far as we know unless we discover matter with negative mass), Emdrive (violates physics, positive results within margin of error), VASIMIR (total meme until we have fusion), solar sails (inferior in almost every way, especially mass). So why isn't this amazing, actually feasible tech given enough attention?

[Anonymous No.11801959]

>>11801956
No clue. Can it break at jupiter?

[Anonymous No.11801964]

>>11801959
Guy in the video says only Neptune has a sufficient field to allow you to brake by yourself. But you just have to go the long way once to build a particle beam and power supply on the other side.

[Anonymous No.11801969]

>>11801868
Damn who the fuck wants solar sails if we could have this instead?!
have a bump for the thread.

[Anonymous No.11801973]

>>11801951
Even the fancy 0.5g superconducting version needs less than 100kW of power and less than a kilometer of superconducting wire. TWR -including power supply- is 10x better than Hall thrusters.

[Anonymous No.11801976]

>>11801951
>Developed by John Slough and others [5, 6], the plasma magnet drive has been validated by experimental results in a vacuum chamber and was a NIAC phase 1 project in the mid-2000s [6]. The drive works by initially creating a rotating magnetic field that in turns traps and entrains the charged solar wind to create a large diameter ring current, inducing a large scale magnetosphere. The drive coils of the reference design are small, about 10 centimeters in diameter. With 10 kW of electric power, the magnetosphere expands to about 30 kilometers in diameter at 1 AU, with enough magnetic force to deflect the solar wind pressure of about 1 nPa (1 nN/m2) which produces a thrust in the direction of the wind of about 1 newton (1N). Thrust is transmitted to the device by the magnetic fields, just as with the coupling of rotation in an electric motor
>For a fixed system, the size of the induced magnetosphere depends on the local solar wind pressure. The magnetosphere expands in size as the solar wind density decreases further from the sun. This is similar to the effect of Janhunen’s electric sail [2] where the deflection area around the charged conducting wires increases as the solar wind density decreases. The plasma magnet’s thrust is the force of the solar wind pushing against the magnetosphere as it is deflected around it. It functions like a square-rigged sail running before the wind.

[Anonymous No.11801986]

>>11801956
>Why is such a promising technology so under the radar?
Expensive rockets, basically. You need to get outside Earth's magnetosphere to test it properly, which means TLI or a similar orbit, which means a Delta IV Heavy or a Falcon Heavy. Nobody does lunar smallsat rideshares yet and a big booster costs over $100 million for a dedicated launch. Gateway, Lunar Starship, and surface moon bases will make testing things outside of Earth's magnetosphere much cheaper.

[Anonymous No.11801990]

>>11801969
Exactly. Why fuck around trying to engineer this giant folding sail kilometers wide and nanometers thin when you could just generate a magnetic field 100,000km wide at the flip of a switch? Then you can "furl" your sail by turning off your magnet when you don't want to interact with the particles.

[Anonymous No.11801995]

>>11801986
>Expensive rockets, basically.
So if starship really delivers on its promises we can actually do this? Maybe the lunar gateway can actually have a purpose in testing this instead of being a deltaV tollbooth.

[Anonymous No.11802012]

Bump

[Anonymous No.11802014]

>>11801973
>>11801976
Interesting. If launch costs keep dropping that could be an option to be tested out by some university or individuals.

[Anonymous No.11802020]

>>11801990
>Then you can "furl" your sail by turning off your magnet when you don't want to interact with the particles.
Or you leave the magnet running and stop rotating the coils and it becomes a brake.

[Anonymous No.11802032]

>>11801976
10kW is about what Dawn used for its ion drive, but this thing would have about ten times the thrust, and not consume reaction mass. A truly capable vehicle would have both.

[Anonymous No.11802038]

>>11802020
Based. This thing is amazing. I just really don't understand physics or orbital mechanics enough to know full implications of this technology. Can you "burn" retrograde to fall into the sun's gravity well and travel sunward without particle beams being set up?

[Anonymous No.11802048]

Very interesting.. perhaps DM Elon??

[Anonymous No.11802080]

>>11802038
No. That's the one weakness of this thing relative to "normal" Zubrin style giant-superconducting-hoop magnetic sails. You need some sort of secondary propulsion to move sunward, whether that's particle beams on a remote station or an onboard nuclear engine.

[Anonymous No.11802091]

Scaled down one not used for thrust can protect the crew from radiation.
>The magnetosphere generated by the engine makes a good radiation shield for the charged particles of the solar wind. It should prove to be a good solution for the solar wind, solar flares and even coronal mass ejections (CME). This device could, therefore, be used for human flight to reduce radiation effects.

[Anonymous No.11802097]

It's called a solar sail and it has to be incredibly light.
https://science.nasa.gov/science-news/science-at-nasa/2008/31jul_solarsails/

[Anonymous No.11802103]

>>11802080
Oh well, all the other benefits make up for it. Deep space and interstellar probes are feasible. Starship should be good enough to set up infrastructure on Mars. It's said in the video Phobos and Deimos are ideal locations for a particle beam array. Imagine how great of a Mars colony you could have with one week transit times each way. It might actually become economically feasible for some Mars manufactured goods to be sold to earth for a profit.

[Anonymous No.11802114]

>>11802097
Solar sails are a meme in comparison. This uses electro magnetic fields as a sail. Magnetic fields weigh 0 grams.

[Anonymous No.11802115]

>>11802097
You could try reading the linked material in the OP. The plasma magnet doesn't need a large physical sail like a photon sail.

[Anonymous No.11802143]

>>11802114
Laser propelled light sails aren't a meme though.

[Anonymous No.11802154]

>>11802143
Compared to a plasma magnet sail they absolutely are. Power to thrust density sucks, thrust per gram sucks, beam diffraction sucks. If you want beamed power to be competitive with a plasma magnet over multi AU distances you need a soliton cannon like PROCSIMA.

https://www.nasa.gov/directorates/spacetech/niac/2018_Phase_I_Phase_II/PROCSIMA/

[Anonymous No.11802166]

>>11802154
Laser powered light sails are much better for interstellar travel

[Anonymous No.11802175]

How does plasma even get collected from the solar winds?

[Anonymous No.11802178]

>>11802166
Can a plasma magnet sail send interstellar probes to 0.20c in ten minutes?

[Anonymous No.11802198]

>>11802166
You actually need a magsail anyway to slow down when you get there, or a heavy physical shield. Photon sails can't brake relativistic velocities on starlight alone.

>>11802175
It doesn't get "collected" per se. The plasma magnet sail is a cylinder made of two pairs of saddle coils that rotates. It magnetically couples to the plasma around it without needing a physical connection using the same mechanism as the rotor-stator connection of an electric motor. This magnetizes the nearby plasma and causes it to deflect against the solar wind, thus transmitting thrust back across that magnetic coupling to the spacecraft.

[Anonymous No.11802211]

>>11802198
What energy do the motors use?

[Anonymous No.11802218]

>>11802198
Yeah I know, but you can set up another laser array at the destination eventually. Also, laser propelled light sails are great for the type of flyby missions planned by breakthrough starshot.

[Anonymous No.11802229]

>>11802211
>What energy do the motors use?
Same as any other spacecraft component, regular electricity from solar panels or an RTG or a reactor.

[Anonymous No.11802236]

>>11802218
>Yeah I know, but you can set up another laser array at the destination eventually.
So it's better to just do a mag sail to start with since you'll need to get your meme lasers into position anyway
>Also, laser propelled light sails are great for the type of flyby missions
Flybys are cringe. Orbit is based

[Anonymous No.11802249]

>>11802236
>Flybys are cringe. Orbit is based
This. I can't wait to hurl a plasma magsail at Neptune and put a long term probe in orbit. Imagine years of modern high-res data about the other blue planet.

[Anonymous No.11802274]

>>11802249
Neptune Cassini when?

[Anonymous No.11802452]

>>11802236
>Flybys are cringe. Orbit is based
Flybys are fine for a first interstellar mission, especially if it means the probes get there in 20 years, not 200

[Anonymous No.11802461]

>>11802249
I do agree though about using the plasma mag sail for interplanetary probes.

[Anonymous No.11802640]

>>11802080
>>11802103
Here's a good partner engine for manned flights.

http://www.projectrho.com/public_html/rocket/enginelist.php#serpsec

[Anonymous No.11802732]

Things you won't see in your life: human space beyond Mars.

There, accept it and move on.

[Anonymous No.11802743]

>>11802732
>he doesn't know about Elon's Ceres plans
Doomers truly are the worst

[Anonymous No.11802764]

>>11802732
The entire point of this thread is that we already have the technology to do that if we can build rotating habs.

[Anonymous No.11802770]

Also, all of the assumptions made in the article are assuming a 10kW solar array. American nuclear submarines can produce 165 MWe of power with fission reactors. If meme techs like fusion or super conductors ever take off plasma magnetic sails just get better.

[Anonymous No.11802775]

>>11802770
The 0.5g model assumes a 30m magnet diameter made of superconducting wire.

[Anonymous No.11802786]

>>11801868
I can't see anything wrong with this plan
And that makes it very suspicious

I cannot recognize any attempt at progress without any challenges from people concerned about its downside

What's the disadvantage of this compared to our current propulsion methods.
Speak or be labeled a scam

[Anonymous No.11802795]

>>11802764
> if we can just invent things we don't have then it's possible
BRAVO

[Anonymous No.11802812]

>>11802786
>What's the disadvantage of this compared to our current propulsion methods
You can't accelerate in any direction other than directly away from the sun. It just so happens that applying ludicrous amounts of delta-v in this direction makes most missions a lot cheaper since it cuts a big fat chunk out of your propellant budget.

[Anonymous No.11802822]

>>11802775
Yeah but that's the insane expanse tier numbers. It said with conventional technology Mars in two months which is great compared to the cucked 8 month Hohmann transfer orbit
>Coupling a more modest velocity of just 10’s of km/s with the function of a MAC, a craft could reach Mars in less than 2 months and aerobrake to reach orbit and even descend to the surface. All this without propellant and a very modest solar array for a power supply.
Also, how practical is it to cool superconductors in the vacuum of space? It must be more practical than on earth right?
>>11802786
We needed larger rockets to test it by taking the payload beyond earth's magnetosphere. Can only go in the direction of the solar wind until proper infrastructure is in place. So you'll need chemical or ion drive or something like that on the way home. But otherwise it really seems like it's the best all around that's possible today.

[Anonymous No.11802825]

>>11802770
Wait,what if you could supply 10+ MW to a Plasma Mag-Sail? Would it BTFO every other propulsion design for intra-solar system missions?

[Anonymous No.11802838]

>>11802812
>>11802822
>no controls
Then that makes it useless for vital transport of humans and resources because no one's gonna trust that there would be no errors in the initial calculation

I'll take it for launching mass scouting drones for gathering information both within the Oorth cloud and beyond. But for human transport, the risk far exceeds the benefit.

Money is cheap
Lose humans and your entire name get tarnished and you lose budget

[Anonymous No.11802850]

>>11802838
Wtf are you talking about? You can control it. You can turn the field on or off at will, or stop the rotation to make it a brake. Currently you can only go in the direction of the solar wind while the sail is "hoisted" but particle beams can push you in the other direction. Also
>Making the plasma magnet thrust directional
>A single magnetosphere cannot deflect the solar wind in any significant directional way, which limits this drive’s navigational capability. However, if the magnetosphere could be shaped so that its surface could result in an asymmetric deflection, it should be possible to use the drive for tacking back to the inner system.
>Figure 5 shows an array of plasma magnets orientated at an angle to the solar wind. The deflection of the solar wind is no longer symmetric, with the main flow across the forward face of the array. Under those conditions, there should be a net force against the grid. This suggests that like a solar sail, orientating the grid so that the force retards the orbital velocity, the craft should be able to spiral down towards the Sun, offering the possibility of a drive that could navigate the solar system.

[Anonymous No.11802856]

>>11802822
>Also, how practical is it to cool superconductors in the vacuum of space? It must be more practical than on earth right?
Yep. YBCO is an extant superconductor that works well for this application, particularly because by design the plasma magnet self-orients to put the rest of the spacecraft between itself and the sun. It's a lot better than the original attempt at a magnetic sail which required a 50km diameter hoop of the stuff with a ton of thermal shielding since it was exposed to direct sunlight.

>>11802838
The plasma magnet is safer than chemical rockets because it's impossible to steer incorrectly, trivial to shut off, and doesn't strap the crew to a giant bomb. The only thing you need to calculate correctly is the launch window, and if you can't do that no engine will save you.

>>11802850
I'm not a fan of that design because you need multiple 10km+ long shroud lines back to the ship and a system of 10km long spars to keep them spaced properly. You lose a lot of the mass budget advantage versus a regular magsail, and it's not faster than carrying along an NTR or a fusion torch for the trip home.

[Anonymous No.11802859]

>>11801976
oh interesting,slough is mostly focused on his fusion power company Helion energy these days. cool guy, very smart.

[Anonymous No.11802865]

>>11802850
>>11802856
And how fast does this plasma sail get set up?
It's a plasma so I presumed that it needed a lot of power to kickstart the reaction?
Also, can this thing enter and leave the atmosphere safely?

You guys are just giving me too much promises my senses are telling me that this is a scam with extremely deadly consequences.

[Anonymous No.11802867]

>>11802154
lol imagine if this gets momentum, the headlines will be great

>USA building a LASER DEATH CANNON IN SPACE

it will be a nightmare

fuck the media

[Anonymous No.11802885]

>>11802859
He gave up on the Plasma Magnet Sail too early, IMO, in favor of the Q-drive, which has a bunch of hand wavey bullshit.
>hey guys what if we had a magic energy converter that always expelled propellant at our ship's current velocity rather than a fixed velocity
>and what if we used a reverse e-sail to siphon electricity out of the solar wind to power it

>>11802865
You could try reading the fucking article linked in the OP that explains how it works. The plasma is the existing plasma of the solar wind. The plasma magnet drive doesn't have to physically collect it, just stir up a magnetic field. The entire thing can be powered with 10kW, or the equivalent draw to seven home microwave ovens. The extra fancy superconducting 30m-diameter version would probably not be capable of reentry because it would burn up in the atmosphere, but with the thrust values we're talking about here it's perfectly sufficient to carry along a Starship or two for landing. The smaller 10kg version actually could be retracted back inside a capsule and land safely so long as you didn't land ON it.

[Anonymous No.11802901]

>>11802856
>YBCO
Cool. How do you cool it, liquid nitrogen? It seems like most of the problems with superconductors on earth don't apply in space if you're not in the sun.
What's your ideal propulsion method for going "upstream" that's possible with current tech? I figured hall effect considering you're already generating electricity.
>>11802865
Watch the video and read the article in the OP. It goes over the benefits and limitations. The video presentation is by this guy, https://en.wikipedia.org/wiki/Jeff_Greason
He says significant fraction of c is possible.

[Anonymous No.11802905]

>>11802885
>>11802901
Ok, I'm reading it.
Does this say anything about how much mass it can transport?

[Anonymous No.11802914]

>>11802901
Zubrin seemed to think that solid shielding would be enough for even multi-km strands of wire. I forget the exact makeup from the papers but it was pretty compact.

>>11802905
IIRC that's basically power limited. The 10kW / 1m toy version can move about 10,000kg of spacecraft, which is more than the dry mass of a Crew Dragon capsule. Larger superconducting plasma magnets can scale up very well. At worst you can do a multi-magnet shroud like in >>11802850 and scale almost indefinitely.

[Anonymous No.11802918]

looks cool

[Anonymous No.11802925]

>>11802905
>Does this say anything about how much mass it can transport?
Depends on how much you scale it. But it has the best thrust to mass ratio, see>>11801976
Also
>As the solar wind operates out to the heliopause, about 80 AU from the sun, the acceleration from a nuclear powered craft is constant and the craft continues to accelerate without the tyranny of the rocket equation. Assuming a craft with an all up mass of 1 MT (700 kg nuclear power unit, 10 kg engine, and the remaining in payload), the terminal velocity at the heliopause is 150 km/s. The flight time is 4.75 years, which is a considerably faster flight time than the New Horizons and Voyager probes.
>In his TVIW talk [1], Greason suggested that the 10kW power supply could propel a 2500 kg craft with an acceleration of 0.5g, reaching 400-700 km/s in just half a day. Greason [i] suggested that with this acceleration, the FOCAL mission for gravitational lens telescopes requiring many craft should be achievable. *

[Anonymous No.11802990]

Ok, I'm reading and watching and what?

>it can allow the spacecraft to accellerate to 420km/s in just a day
>allowing us to reach Mars in 5 days
>but Mar's magnetic force is not powerful enough to stop the plasma sail
>so we have to travel all the way to Neptune just to reduce the speed and orbit back into Mars with a much more manageable speed

>which would take 4 months to reach Neptune.

...
Seriously?

[Anonymous No.11803001]

>>11802990
If you keep watching, he says we'll need particle beams to decelerate at Mars which we'll have to travel to Mars "the long way" with something like starship to set up that infrastructure. Neptune is the only planet which has a magnetic field strong enough to fully decelerate. But it's already viable for deep space probes and interstellar probes. It's especially great for interstellar travel since the solar wind of the other star will let you brake. You don't have to go to Neptune to go to Mars it's a different mission.

[Anonymous No.11803011]

>>11803001
>we'll need particle beams to decelerate at Mars which we'll have to travel to Mars "the long way" with something like starship to set up that infrastructure. Neptune is the only planet which has a magnetic field strong enough to fully decelerate
Happily, Starships launched from Mars also get us Ceres, Jupiter, and Saturn, so the hardest planet to colonize would probably be Uranus.

[Anonymous No.11803019]

>>11802990
It's like flying, sometimes you have a stopover way out of the way because it's the hub for the airline and what should be a 1 hour flight turns into two 3-hour flights and a few hours in between.

[Anonymous No.11803022]

>>11803019
>Neptune becomes the transportation hub of the outer system
This is a good future.

[Anonymous No.11803034]

Ok, I finished it and now gets a the bigger picture of its disadvantages

Main flaws is
1. Technology does not exist yet
2. It is completely untested.
3. Requires already existing space infrastructures in order to be a viable method of transportation

Much of the research spoke about how it can accelerate a space craft at ground breaking speeds at cheaper fuel
However, due to the lack of testing, there was not a single mention of how the spacecraft itself can be constructed with what materials.

How do handle safety for example considering that it's a massive sail travelling at high speed. Space junk would be an even greater serious threat

I believe a research into electromagnetic shielding is needed as a first layer of defense

The entire research is very promising.
However, I can only presume that this would be attempted at 2150's because it just demands too much technological break throughs

Particle accelerators already exists but not outside of lab. Lasers exists too but they are in infrared. And you want them to already be stationed in Phobos and Daimos to be serve as pit stops for the solar magnetic plasma sails?

It's a great concept but it's understandable why not much attention is being given. We need to finish the first floors before climbing up the roof

For now, we need to conquer our need for Nuclear Fusion as it's the only way to provide power to Lunar and Martian colonies

[Anonymous No.11803047]

>>11803034
>How do handle safety for example considering that it's a massive sail travelling at high speed. Space junk would be an even greater serious threat
>I believe a research into electromagnetic shielding is needed as a first layer of defense
You don't get it still. The physical component is a set of magnets less than 50m across for the extra big version, a rotor, and a power supply. The sail IS the magnetosphere. The induced magnetic field itself provides shielding in the direction of travel, or unidirectionally in brake mode.

[Anonymous No.11803054]

>>11803047
I'm talking about electromagnetic shielding that would repulse any space junk that can pose a threat to the ship.

It's already under research for protecting military vehicles and may be used to clean up space junk and repulse them to burn in the atmosphere

[Anonymous No.11803062]

>>11803034
>1. Technology does not exist yet
Is this concern trolling? The technology does exist. It's two rotating magnetic coils.
>2. It is completely untested.
It was tested by nasa per the video
>3. Requires already existing space infrastructures in order to be a viable method of transportation
No it doesn't. It's 100% viable for a new horizons type mission, any deep space probe with no infrastructure set up at all.
>How do handle safety for example considering that it's a massive sail travelling at high speed. Space junk would be an even greater serious threat
Its not a physical sail, it cannot be damaged or overheated, it's a magnetic field. There is no "space junk" in deep space, it would not encounter any more debris than a more conventional system.

[Anonymous No.11803065]

>>11803062
>There is no "space junk" in deep space
There is, at relativistic speeds, but that's what the sail is for, shielding and braking.

[Anonymous No.11803073]

>>11803062
Nigga, V1 rockets are not space shuttles.
You cannot call rotating magnetic coils a magnetic plasma sail

It's not just space junk. Space debris, space dust, alpha particles, solar flares, extreme temperature fluctuations and so on

[Anonymous No.11803080]

>>11803073
>Developed by John Slough and others [5, 6], the plasma magnet drive has been validated by experimental results in a vacuum chamber and was a NIAC phase 1 project in the mid-2000s [6]. The drive works by initially creating a rotating magnetic field that in turns traps and entrains the charged solar wind to create a large diameter ring current, inducing a large scale magnetosphere. The drive coils of the reference design are small, about 10 centimeters in diameter. With 10 kW of electric power, the magnetosphere expands to about 30 kilometers in diameter at 1 AU, with enough magnetic force to deflect the solar wind pressure of about 1 nPa (1 nN/m2) which produces a thrust in the direction of the wind of about 1 newton (1N). Thrust is transmitted to the device by the magnetic fields, just as with the coupling of rotation in an electric motor (figure 2).
They already made a small version. The basic version requires no new technology.

[Anonymous No.11803085]

>>11803080
Technology for the sail
Not the technology that allows it for transport. Safely

[Anonymous No.11803090]

>>11803085
The magnetic field itself shields the craft. Even if it doesn't and we never ever solve shielding, it can keep accelerating to the fastest safe speed, faster than everything we have today.

[Anonymous No.11803099]

>>11803090
I know.
But the cargo is always more important than the ship

First test it on delivering drones to Neptune or Europa. Then we'll talk.

[Anonymous No.11803113]

>>11803099
Sure. My point is that this hasn't even been given an opportunity yet. Current technology will allow a Neptune orbiter to arrive at record speed with record mass. Hopefully starship minimum viable product is developed asap so we can start space testing and missions.

[Anonymous No.11803377]

>>11803113
>Hopefully starship minimum viable product is developed asap so we can start space testing and missions.
Oldspace fuckery wasted 50 years of time on "build more expendable rockets :DDDDD" instead of real advancement. Fucking Jews.

[Anonymous No.11803405]

>>11803377
If all progress didn't stop after apollo things would be so much better. All I want to know is if there are habitable planets in the Centaur system(s). If we knew there were, we could have already been on our way by now and humanity would never die out then.

[Anonymous No.11803710]

Would this make generation ships possible? Could we use it to accelerate ships that then detach and fly on their own, breaking by entering atmosphere of their target planet?

[Anonymous No.11803721]

>>11803710
Yeah. Only you wouldn't detach. You'd turn off the field after you leave the heliosphere, then turn it back on to decelerate against the solar wind of destination star.

[Anonymous No.11803737]

Wow this is mind blowing, surprised Elon hasn't picked this up. Really need a fucking test flight to make sure but it seems 100%.

Also friendship ended with Mars, now Neptune is my best friend. Fuck Inners.

[Anonymous No.11803742]

>>11803721
How long would a breaking maneuver take? Would it be like the expanse where they constantly accelerate until half way, then flip around to decelerate the rest of the way?

[Anonymous No.11803764]

Why Neptune and not Jupiter? I thought Jupiter had a gigachad tier magnetic field.

[Anonymous No.11803775]

>>11803737
Yeah I hope they use it. Even if they don't use it for propulsion, it has uses for radiation protection and aerocapture.
>>11803742
The guy in the video says you can get 0.5 G acceleration, which I presume would be the 30m superconducting coil. Which is absolutely insane and wouldn't take long to decelerate from even relativistic speeds.

[Anonymous No.11803814]

>>11803775
Sounds too good to be true, especially if it's so cheap and easy to make. Wouldn't it be easy to make smaller, private spacecrafts with it too? Like some private yacht to cruise around... Obviously we don't have the infrastructure but damn. Really feels like The Expanse in here. And also quite the romantic thought that once again humanity shall use sails to explore the unknown.

[Anonymous No.11803834]

Holy shit this would crack open the solar system like a fucking egg. One week to Mars, four months to Neptune? Get me off this shithole planet.

Fuggggggg I've been burned too many times by promising propulsion tech.

[Anonymous No.11803893]

>>11803814
I know. I love the idea of a new age of the sail. The idea of solar system "geography" and currents is extremely kino.
>>11803834
I know, I want to leave this planet and explore the cosmos more than anything. I've been burned by memes too. I fell for the Emdrive. I fell for the "just wait until VASIMIR is done, Mars mission 2033, you'll see." I'm sick of the promises never panning out. So I posted this so if it's bullshit a physicist anon could btfo it. So far so good, at least Elon is delivering on his promises worst case scenario.

[Anonymous No.11803907]

>>11803764
Yeah it seems like it would be Jupiter. Maybe you can but I'm just going off of what the presenter said in the video. Maybe someone is able to prove otherwise?

[Anonymous No.11804009]

>>11803893
>I love the idea of a new age of the sail
It makes so much sense too. Sailing allowed us to go everywhere long before we used anything else. It feels like a very logical progression to go back to the roots of how we used to get around.

[Anonymous No.11804051]

>>11802732
>he thinks we'll ever touch Mars

[Anonymous No.11804151]

>>11803737
This is what Elon will use to get to the outer solar system. The starships will be used as habitation modules for the crew during flight, as well as landing ships for the moons out there.

[DoctorGreen !DRgReeNusk No.11804296]

>>11801976
interesting

[Anonymous No.11804610]

>>11804151
The 18m Starship variants would basically be like rotisserie chickens, spinning to create crew gravity.

[Anonymous No.11804680]

>>11804009
>tfw treasure planet was real
>>11804051
>he doubts Elon after he btfo the haters with Falcon 1, Falcon 9, the Merlin engine, Falcon Heavy, the Raptor engine, dragon 1, dragon 2, landing, landing at sea, reuse, and starlink.
Doomers are never gonna make it.
>>11804151
Just for the radiation protection and aerocapture Elon should find it useful.
>>11804610
The version that has the most insane numbers is 30m. We'll need a 30m starship after the 18m one.

[Anonymous No.11804737]

>>11804680
The 30m Starship could carry pre fabbed saddle coils for the high end plasma magnet sail too.

[Anonymous No.11804801]

>>11801868
It can only move away from the sun.

[Anonymous No.11804850]

>>11804680
>>tfw treasure planet was real
We even get the moon as a spaceport. It's got low gravity and is outside Earth's magnetosphere, so all you need is a cheapass reusable ISRU Al-LOX rocket "pilot boat" booster or a mass driver to launch your payloads to lunar orbit. Then the plasma magnet sail is unfurled and off you go.

[Anonymous No.11804861]

>>11804801
>It can only move away from the sun.
Only until particle beams are set up for sunward travel. And particle beams are great compared to lasers because there's no defraction. But in the mean time, just carry another propulsion system on board if it's a mission that must return. However, this is great for the outer solar system, and interstellar probe that can actually enter orbit, and missions like FOCAL.
https://en.wikipedia.org/wiki/FOCAL_(spacecraft)

[Anonymous No.11804877]

>>11802822
>Also, how practical is it to cool superconductors in the vacuum of space?
Very interesting question, one I've pondered a lot myself. The answer is it's hard. Anything hit by sunlight around 1 AU will heat to 100 Kelvin. The James Webb Space Telescope uses passive cooling made up of a five layer shield that reduces heat flux to limit the telescopes temperature to 40 Kelvin. You could reduce heat flux even more by adding more layers, but your ring is 30km wide, so eh.

You definitely can't use conventional metallic superconductor wires for this, they need to be way to cold. High-temperature superconductors are probably a must for this and they're kind of a meme. Afaik you can't really make wire out of any of them and they handle current and magnetic fields very badly compared to low-temp SCs.

[Anonymous No.11804890]

>>11804850
>We even get the moon as a spaceport.
The moon as the gateway to the solar system is top tier kino. Take a nice leisurely ride from earth, fuck around in lunar gravity for a few days, play golf, then get ready to go to Mars and beyond.
>ISRU Al-LOX
Redpill me on this? What's the performance like? I wish the moon had methane so that starship cold refuel there.
>mass driver to launch your payloads to lunar orbit
Since you can have infinite solar power with panels placed on a peak of eternal light by the south pole, near eternally shaded crators which have water ice, it seems like the ideal place for a base. Mass drivers are great on the moon because no atmosphere and no ISRU needed since carbon is scarce and hydrogen is shit. Does anyone know how long the track would have to be to make acceleration safe for humans?

[Anonymous No.11804900]

>>11804890
>Redpill me on this? What's the performance like?
SRB tier (2800m/s exhaust velocity, 285 Isp) but it's literally just cracking lunar regolith with electricity and chilling the O2 so it's cheap.

http://www.asi.org/adb/06/09/03/02/095/al-o-propellants.html

Until you can build a mass driver it's cheap.

[Anonymous No.11804908]

>>11804877
>The answer is it's hard. Anything hit by sunlight around 1 AU will heat to 100 Kelvin.
Would a shade like the ones imagined for orbital fuel depots work?
>You could reduce heat flux even more by adding more layers, but your ring is 30km wide, so eh.
Anon you misunderstand. The 30km wide ring is just the magnetic field diameter at 1AU. To get a field like that the coil needs only to be 10cm with 10kW running through it.
>You definitely can't use conventional metallic superconductor wires for this, they need to be way to cold. High-temperature superconductors are probably a must for this and they're kind of a meme. Afaik you can't really make wire out of any of them and they handle current and magnetic fields very badly compared to low-temp SCs.
I hate how superconductors are a fusion tier meme of "just around the corner." Wish we could make them work at earth temps.

[Anonymous No.11804914]

>>11804908
All we need is to keep them cooled below ~150K and that's much more feasible.

[Anonymous No.11804961]

>>11804900
>SRB tier (2800m/s exhaust velocity, 285 Isp) but it's literally just cracking lunar regolith with electricity and chilling the O2 so it's cheap.
Yeah Lunar gravity is so low we really don't need much. Just to carry the craft to orbit, let it deploy the mag sail, then return to the surface to bring the next craft
>http://www.asi.org/adb/06/09/03/02/095/al-o-propellants.html
Very interesting. Is it known if Alox is conducive to reuse? Seems like it could really fuck up an engine, although it's sufficient to get the job done at least once which might be all that we need.

[Anonymous No.11804971]

>>11804961
The research was done in 1996 so I don't think anyone was thinking about reusability other than the Shuttle at the time. Might be worth researching.

[Anonymous No.11804979]

>>11804971
Very forward thinking for 1996. He didn't fall for the hydrogen meme like everyone else did. But yeah more research is needed. It would be great to have access to space from the lunar surface independently from any supplies from earth.

[Anonymous No.11804988]

>>11804908
>To get a field like that the coil needs only to be 10cm
I did misunderstand. Well, that makes this a LOT easier.
>>11804914
Yeah, if the ring is that small it can easily be made with HTS. Quick google search tells me that YBa2Cu3Oy at 77 Kelvin can handle 7750A/cm^2 in a 2 Tesla magnetic field, which seems like it's more than enough to handle 10kW (where does this number come from by the way? I'd be more interested in the current you need and exactly how strong the magnetic fields involved are) to me.

[Anonymous No.11804989]

>>11804979
>independently from any supplies from earth.
You'll still need a crapton of volatiles to keep people alive. Hydrogen, oxygen, nitrogen, phosphorus, carbon, etc. Keeping your fuel supply separate from your life support cycle is the big win.

[Anonymous No.11805064]

>>11804988
>YBa2Cu3Oy at 77 Kelvin can handle 7750A/cm^2 in a 2 Tesla magnetic field, which seems like it's more than enough to handle 10kW (where does this number come from by the way? I'd be more interested in the current you need and exactly how strong the magnetic fields involved are) to me.
It's from the website in the OP
https://www.centauri-dreams.org/2017/12/29/the-plasma-magnet-drive-a-simple-cheap-drive-for-the-solar-system-and-beyond/
>Developed by John Slough and others [5, 6], the plasma magnet drive has been validated by experimental results in a vacuum chamber and was a NIAC phase 1 project in the mid-2000s [6]. The drive works by initially creating a rotating magnetic field that in turns traps and entrains the charged solar wind to create a large diameter ring current, inducing a large scale magnetosphere. The drive coils of the reference design are small, about 10 centimeters in diameter. With 10 kW of electric power, the magnetosphere expands to about 30 kilometers in diameter at 1 AU, with enough magnetic force to deflect the solar wind pressure of about 1 nPa (1 nN/m2) which produces a thrust in the direction of the wind of about 1 newton (1N). Thrust is transmitted to the device by the magnetic fields, just as with the coupling of rotation in an electric motor

[Anonymous No.11805070]

>>11805064
>It's from the website in the OP
I know, unfortunately the sources are all very inaccessible.

[Anonymous No.11805073]

>>11805064
>which produces a thrust in the direction of the wind of about 1 newton (1N)
That's equivalent to a 300MW (300,000kW) photon rocket or beamed laser sail with 10kW of input power. That's quite some efficiency gain.

[Anonymous No.11805104]

>>11805070
Here are the quoted sources in the article on that point.
Slough, John. “The plasma magnet for Sailing the Solar Wind.” AIP Conference Proceedings, 2005, doi:10.1063/1.1867244.
Slough, John “The plasma magnet” (2006). NASA Institute for Advanced Concepts Phase 1 Final Report.

[Anonymous No.11805115]

>>11805104
PDF download links are available.

>Slough, John. “The plasma magnet for Sailing the Solar Wind.” AIP Conference Proceedings, 2005, doi:10.1063/1.1867244.
https://aip.scitation.org/doi/abs/10.1063/1.1867244
>Slough, John “The plasma magnet” (2006). NASA Institute for Advanced Concepts Phase 1 Final Report.
http://www.niac.usra.edu/files/studies/final_report/917Slough.pdf

[Anonymous No.11805116]

>>11801868
Didn’t know this existed but neato I guess

[Anonymous No.11805137]

Can anyone clear up the max speed? The video seems to say that you can go faster than the solar wind. However, the article says
>As the sail has a maximum velocity of that of the solar wind, a probe accelerating at 0.2g would reach maximum velocity in a few days, and pass by Mars within a week. To reach a velocity of 20 km/s, faster than New Horizons, the Plasma magnet would only need to be turned on for a few hours. Clearly, the scope for using this drive to accelerate probes and even crewed ships is quite exciting.
But Wikipedia says
>A common misconception is that a magnetic sail cannot exceed the speed of the plasma pushing it. As the speed of a magnetic sail increases, its acceleration becomes more dependent on its ability to tack efficiently. At high speeds, the plasma wind's direction will seem to come increasingly from the front of the spacecraft. Advanced sailing spacecraft might deploy field coils as "keels", so the spacecraft could use the difference in vector between the solar magnetic field and the solar wind, much as sailing yachts do.
https://en.wikipedia.org/wiki/Magnetic_sail

[Anonymous No.11805146]

>>11805115
Thank.

[Anonymous No.11805169]

>>11805137
>The video seems to say that you can go faster than the solar wind.
The video talking about interstellar missions is assuming some other propulsion mechanism to get up to relativistic speeds and then using the plasma magnet sail as a brake while approaching the distant star. The downside of plasma magnet sails is that they make a big round field so you can't set them perpendicular to the wind like a hoop sail, but you also don't have to pay the financial or mass penalties for multiple kilometers of superconducting wire.

[Anonymous No.11805193]

>>11805137
Curious. The maximum velocity argument seems logically sound to me, when you reach the velocity of the solar wind it will seem stationary from your rest frame and only high-velocity outlier particles can transfer any more momentum to you, so your acceleration slows down to practically zero. I don't know how you'd get around that with angling and magnetic fields and I suspect wikipedia is simply wrong.

[Anonymous No.11805216]

>>11805193
>I suspect wikipedia is simply wrong.
They're actually citing Zubrin's original 1990 paper on circular magnetic sail hoops. Read that if you haven't.

http://www.niac.usra.edu/files/library/meetings/fellows/nov99/320Zubrin.pdf

[Anonymous No.11805283]

>>11805169
So would particle beams get the craft up to relativistic speeds?
>>11805216
So is Zubrin's design more maneuverable even though it's much more massive and difficult to construct?
Also, before we use this for propulsion, I'm very interested in the aerobrake capabilities. The article says
>A simple dipole magnet magnetosphere can be used as a very effective aerocapture shield. The shield is just the plasma magnet with coils that do not rotate, creating a magnetosphere of a diameter in meters, one that requires the injection of gram quantities of plasma to be trapped in the magnetic field. As the magnetosphere impacts the atmosphere, the neutral atmosphere molecules are trapped by charge exchange. The stopping power is on the order of kilonewtons, allowing the craft to achieve orbit and even land without a heavy, physical shield. The saving in mass and hence propellant is enormous. Such aerobraking allows larger payloads, or alternatively faster transit times. Because the magnetoshell is immaterial, heat transmission to the shield is not an issue. The mass saving is considerable and offers a very cost-effective approach for any craft to reduce mass, propellant requirements or increase payloads. This approach is suitable for Earth return, Mars, outer planets, and Venus capture.
Would this be good enough for starship? I know they tinkered with the idea of sweating methane. But if they want rapid reuse, eliminating a physical heat shield and tiles would be perfect. Could they use a methane fuel cell to power the field?

[Anonymous No.11805302]

>>11805283
>So would particle beams get the craft up to relativistic speeds?
Yes.
>So is Zubrin's design more maneuverable even though it's much more massive and difficult to construct?
It's more maneuverable but also much weaker in straight-line thrust away from the sun because you're limited to a magnetic field the size of the hoop you construct rather than a 10km^3 sphere. The nice thing about the plasma magnet sail is that it's so light you can add other propulsion systems to shore up the weak points, like using the generator cycle of a bimodal NTR to power the thing and then using the NTR's thrust cycle for burns perpendicular to the solar wind, or for travel within a large magnetosphere like Earth or Jupiter.
>Also, before we use this for propulsion, I'm very interested in the aerobrake capabilities
Literally just add a <100W rotor to the brake version and you have the sail. There's no point in half assing it.

[Anonymous No.11805306]

>>11802048
I already know about it, thanks though.

[Anonymous No.11805312]

>>11805306
Oh shit. Hi, Elon.

>>11805283
>Would this be good enough for starship?
Maybe for Mars capture. It would probably burn up in the atmosphere on Earth reentry if left exposed.

[Anonymous No.11805327]

>>11803001
>Neptune is the only planet which has a magnetic field strong enough to fully decelerate.
Doesn't Jupiter has the strongest magnetic field of all?

[Anonymous No.11805341]

>>11805302
>Yes.
Hello Alpha Centauri. I really thought practical interstellar probes were not at all feasible with current technology aside from unwieldy solar sails
>The nice thing about the plasma magnet sail is that it's so light you can add other propulsion systems to shore up the weak points, like using the generator cycle of a bimodal NTR to power the thing and then using the NTR's thrust cycle for burns perpendicular to the solar wind, or for travel within a large magnetosphere like Earth or Jupiter.
Amazing. I didn't know NTR could generate power as well, I thought it was only a propulsion implement. Magnetic plasma sail plus NTR can get everywhere in the solar system.
>Literally just add a <100W rotor to the brake version and you have the sail. There's no point in half assing it.
Yeah I agree it's superior, but the people in charge of these decisions aside from Elon who is too unpredictable are ultra conservative. I think it would be easier to get them to test it in pieces than a deep space star shot.

[Anonymous No.11805360]

>>11805341
>I didn't know NTR could generate power as well, I thought it was only a propulsion implement.
Anywhere in the ice belt of the solar system, the plasma magnet plus a Triton engine (NTR / LANTR / power generation tri modal engine, P&W designed for NASA) gets you a damn solid thrust vs. Isp sliding scale. Earth and Mars lift are obviously where Starship reigns supreme.
>I think it would be easier to get them to test it in pieces than a deep space star shot.
You can put one of these in a fucking Cubesat. We're just waiting for lunar Cubesat rideshares to become viable and then I'm personally going to start raising money to build one.

PDF link for the Triton engine:
http://hdl.handle.net/2060/19950005290

[Anonymous No.11805370]

>>11805327
That's what everyone's saying ITT but Jeff Greason, the presenter in the video, said only Neptune works. However, he didn't cite anything. It would be nice if someone could do the math. Being able to go direct to Jupiter and brake would be game changing, especially since the field can protect the crew from the radiation.

[Anonymous No.11805407]

>>11805341
>I really thought practical interstellar probes were not at all feasible with current technology
Nuclear pulse propulsion works too. People often forget about it because it's absolutely insane and the rational brain rejects the idea of using nuclear explosions to hurl people through space, but we do have a viable way to utilize fusion for spaceship propulsion.

[Anonymous No.11805427]

>>11801868
COOL

[Anonymous No.11805443]

>>11805360
>You can put one of these in a fucking Cubesat. We're just waiting for lunar Cubesat rideshares to become viable and then I'm personally going to start raising money to build one.
I'll donate. Thank God SpaceX is making access to space affordable. I think it's down to $5,000/kg, so it shouldn't be too hard considering how small the coils and solar panels can be.
>PDF link for the Triton engine:
>http://hdl.handle.net/2060/19950005290
Thanks. I know hydrogen has the best ISP but storage, boil off, leakage, embrittlement, and tank mass are such problems. I hope efficiency wouldn't take too much of a hit to switch to methane.
>>11805407
>Nuclear pulse propulsion works too. People often forget about it because it's absolutely insane and the rational brain rejects the idea of using nuclear explosions to hurl people through space, but we do have a viable way to utilize fusion for spaceship propulsion.
Very true but that is 100% politically infeasible. The unwashed masses of smoothbrains will never let the politicians do it.

[Anonymous No.11805447]

>>11805306
Please include the word lol in your next tweet if you are actually elon

[Anonymous No.11805461]

>>11805443
>Thanks. I know hydrogen has the best ISP but storage, boil off, leakage, embrittlement, and tank mass are such problems. I hope efficiency wouldn't take too much of a hit to switch to methane.
H2 LANTR has the advantage that all you need for fuel is ice and electricity, which makes ISRU easy, and also doesn't get carbon everywhere. Having to periodically scrub soot out of a nuclear rocket in zero G is not my idea of a good time. If there's a good carbon source in the Jupiter system and you can run it without sooting up the engine then yeah, methane is better.

[Anonymous No.11805637]

>>11805443
space is down to around 2200/kg with block 5 falcon 9 I thought?

[Anonymous No.11805642]

>>11805637
That's low orbit. TLI is still $$$ which is why Israel jewed out on Beresheet and used perigee-boost with RCS to transfer from LEO over like three months.

[Anonymous No.11805645]

This is some EM Drive bullshit again

[Anonymous No.11805663]

>>11805645
It's not, though. It's already demonstrated real usable thrust in a lab. EM Drive still hasn't.

[Anonymous No.11805684]

>>11805642
oh yeah TLI won't be cheap until starship, at which point it might get down to the 30s-50s, which is absurd.

[Anonymous No.11805702]

>>11805645
EM drive has an unknown mechanism of action and it's very dubious it even works at all.
Magnetic sail mechanism of action can be explained at a high level with newtons laws. The details can be explained using our existing knowledge of physics. Magnetic sails have several limitations which preclude them from use as a primary drive in most applications, but they can make long distance travel far more efficient.

[Anonymous No.11805703]

>>11801868
MAYBE BECAUSE THIS GUY IS EXTREMELY BAD EXPLAINING AND THE PICTURES ARE WORTH SHIT

PLS HELP ME UNDERSTAND

watch the video from 3:40 - 5:00. What does he mean? So you take a Stator. You take out the rotating inner parts?(he is very unclear on that) Than you put the WHOLE stator in a conducting liquid? (also very unclear if he is putting the liquid inside it or around it)

3:50 What does he mean "the magnetic field drags the charged particles along with you(?)", with whom? this makes no sense.

Next 6:19, the picture tells me nothing. just the a ratio of size... no pressure for reference... i just have to assume the field gets big enough in the pressure of space? what if it doesnt?

Last question, wouldnt the magnetic fields stability change when the Solar wind hits it and therefore decrease the currents strength?

please help I have no idea about magnets

[Anonymous No.11805718]

>>11805703
Here's a diagram of how it works. Basically you take a cylinder made of four electromagnets, and rotate the cylinder along its axis, and run current through the electromagnets. The conducting fluid is the plasma, either artificial in a lab test or the ambient solar wind plasma in space.
>no pressure for reference
1 nPa
> i just have to assume the field gets big enough in the pressure of space? what if it doesnt?
It does. The plasma size is effectively unbounded in the heliosphere so the same charge creates a field capable of deflecting an equal number of charged particles at any distance from the sun no matter how much volume that requires, thus constant thrust all the way to the heliopause if you leave the sail running.

[Anonymous No.11805746]

>>11801868
the electricity needed to make a magnetic field kilometers wide is to great and the em drive is a reality that exist and was tested and works. it may not be insane thrust but its more realistic than what you put forward

you run into the lifter problem. a lifter can be made and with some high voltage make it go into the air. the problem is that the weight of everything needed to make it actually defy gravity is to much. even if you have a burst of electricity to make your sail you wont be able to make it bigger or maintain it for very long. its not the worst fall back option for a spacecraft i have ever seen but its not what you want as your primary propulsion and the em drive is a better fall back for limited adjustments and minor thrust in a worst case scenario.

the normal physical sail idea sounded better to me honestly. no electricity needed but it still has to be massive

[Anonymous No.11805750]

>>11805718
>rotate the cylinder along its axis
how? mechanically? that would be so unscifi

>1 nPa
you need to tell me rate of pressure decrease too or it has no value

>The plasma size is effectively unbounded in the heliosphere
I dont get it, if the coil rests in a conduction liquid, the plasma will only be able to be the size of the liquid. and since you need a cointainer it can only be the size of the container, why is this not adressedd?

[Anonymous No.11805770]

>>11805750
>how? mechanically?
Yes. The mechanism isn't scifi but the results sure as shit are.
>you need to tell me rate of pressure decrease too or it has no value
Variable with distance from the sun since we're interacting directly with solar wind plasma. At 1AU it drops off from 1nPa to zero at about 10km.
>I dont get it, if the coil rests in a conduction liquid
The plasma IS the conduction fluid. That's the ingenious part here. You only need a container for lab tests on Earth.

[Anonymous No.11805775]

>>11805746
>the electricity needed to make a magnetic field kilometers wide is to great and the em drive is a reality that exist and was tested and works. it may not be insane thrust but its more realistic than what you put forward
All it takes for a 30km diameter magnetic field at one AU is a 10cm coil and 10kW. They already proved it in a lab. Emdrive is a meme that's been disproven experimentally and cannot be explained theoretically.

[Anonymous No.11805795]

>>11805770
>Yes. The mechanism isn't scifi but the results sure as shit are.
desu I wanted to say i dont believe it is mechanically, one can induce a rotating magnetic field with a non-rotating stator... there is no need for mechanical rotation... and it would be a pain to work with for engineers.

>>11805770
>. At 1AU it drops off from 1nPa to zero at about 10km.
still doesnt explain the pictures. Also what is 0nPa supposed to mean for the size of the magentic field if it is unboanded in the heliosphere? infinitely big?

>You only need a container for lab tests on Earth.
What? How? It would escape easily.

[Anonymous No.11805805]

>>11805775
30km sounds much by human standards but is that big enough to propel anything of meaningful size with solar wind?

[Anonymous No.11805812]

>>11805805
>30km sounds much by human standards but is that big enough to propel anything of meaningful size with solar wind?
400km/s Isp goes a really long way.

[Anonymous No.11805827]

>>11805805
>30km sounds much by human standards but is that big enough to propel anything of meaningful size with solar wind?
It's just to show that you can make a massive field with a small coil and tiny amount of electricity. You can scale up the coil, the power, or both to create an even bigger field. A 30 meter superconducting coil makes 100,000km diameter field.

[Anonymous No.11805845]

>>11805805
>30km sounds much by human standards but is that big enough to propel anything of meaningful size with solar wind?
Yes, you can propel a 2500kg spacecraft with that little 10cm coil. It's not much by manned spacecraft standards but it's a decent probe.

[Anonymous No.11805847]

>>11805827
thats also a big number, but maybe it's small in the relevant scale...

because if we have ssuch a big field, it also means the pressure is extremely low, and that means the solar wind source is extremely far away and therefore very little charged particles will hit the "sail", yeah 100,000km is big, but what use is it, if not enough particles hit it. (note that the farther away, the more the particles will be affected by turbulence and not hit the sail in the optimal angle or not?)

[Anonymous No.11805850]

>>11805847
>and that means the solar wind source is extremely far away and therefore very little charged particles will hit the "sail",
Any particle that hits the field moves the entire field, which transfers momentum to the coils. That's how the sail works.

[Anonymous No.11805875]

>>11805850
>Any particle that hits the field moves the entire field,
i dont fully understand, what role does angle of impact play?

[Anonymous No.11805879]

>>11805875
>what role does angle of impact play?
Individual angle of impact averages out to one big vector away from the sun because, again, it's solar wind. This is why you can't steer with it.

[Anonymous No.11806013]

>>11805847
>because if we have ssuch a big field, it also means the pressure is extremely low, and that means the solar wind source is extremely far away and therefore very little charged particles will hit the "sail"
But the sail radius expands as the pressure drops so thrust is constant. From the article:
>A key feature of the plasma magnet is that the diameter of the magnetosphere increases as the density of the solar wind decreases as it expands away from the sun. The resulting expansion exactly matches the decrease in density, ensuring constant thrust. Therefore the plasma magnet has a constant acceleration irrespective of its position in the solar system.

[Anonymous No.11806367]

I'm rewatching the video linked in OP and it looks like you can actually take a 100kg+ payload to Mars in a week with one of these things if you brake it hard enough. It might be worth lashing together a cluster of a dozen Starships and getting there in a month or two instead with full fuel tanks for deceleration and landing.

[Anonymous No.11806419]

>>11802166
so let me bogpill you on PROCSIMA. For interstellar travel using lasers, you need to send a tiny ass payload so that it accelerates within a reasonable distance before the beam gets too spread out. Or you use a laser with a fucking HUGE, 100 km or so, lens to get APERTURE so the beam won't spread out. Now here's the bogpill, PROCSIMA allows you to use a much smaller 1 meter aperture because the particle beam prevents the laser beam from diffracting out to astronomical unit distances.

[Anonymous No.11806452]

>>11801868
if it's so great OP why aren't you working out how to test this fucker instead of fapping about it on 4chan?
>>11805775
it took a while to get a working lightsail even though we knew they should work because of the engineering difficulties of deploying them. There are probably similar engineering challenges to making it work. This smells like it requires superconducting magnets which need to be kept fucking cold. Plasma physics ain't a cakewalk either.

[Anonymous No.11806460]

>>11806452
Money. You can't flight test it inside Earth's magnetosphere. If you have the money for an Earth escape trajectory or TLI launch, please, go for it.

[Anonymous No.11806590]

>>11804890
>The moon as the gateway to the solar system is top tier kino
>The moon as the gateway
>moon gateway
>Lunar Gateway
Oh shit. Has NASA been sitting on this in their back pocket the whole time waiting for Gateway to be ready?

[Anonymous No.11806609]

>>11806460
you don't have to launch if yourself. You just have to show it's a good enough idea that someone should give you money to build and launch it. Show me some fancy CAD drawings and nice math for what a demo mission should look like. What's the minimum mass it takes to test it? If starship actually works, maybe the cost of testing it becomes cheap enough that a bunch of incompetent undergrads can do the test as part of a senior design project.

[Anonymous No.11806657]

>>11806452
>if it's so great OP why aren't you working out how to test this fucker instead of fapping about it on 4chan?
>if you like plasma magnet sails so much name three of their albums
I'm not an engineer. I'm just trying to get people talking about it, make sure it's not a scam, so maybe someone at nasa or SpaceX or some other new space company makes it. If there's a crowd funded cubesat or something I'll donate.
>it took a while to get a working lightsail even though we knew they should work because of the engineering difficulties of deploying them. There are probably similar engineering challenges to making it work. This smells like it requires superconducting magnets which need to be kept fucking cold. Plasma physics ain't a cakewalk either.
It was already built and tested, it works. See the 2006 study>>11805115

[Anonymous No.11806695]

>>11806609
>What's the minimum mass it takes to test it?
A 6U Cubesat full of batteries and a 10cm set of coils on the forward end ought to do it, assuming they ever send a Cubesat ride share bus out to the moon. Starship service to Gateway absolutely makes this affordable to test.
>Cubesat bus takes you out past the magnetosphere, oriented properly for mission assuming the drive works
>aft antenna deploys for comms back to Earth
>verify link
>begin sending telemetry
>energize magnet coils and start rotating them
====assumption of proper drive function begins here====
>drive is energized for a day, accelerating the Cubesat to solar wind velocity on a lithobrake-intercept course for one of the outer planets or their moons
>drive powered off to save battery power
>wait until within visual range of destination planet
>power up forward cameras
>start taking pictures and sending them back to Earth
>repeat until lithobrake intercept with target

[Anonymous No.11806769]

>>11806695
naw that's great and all, but you got any math to show you can actually do it with a 6U cubesat?
>>destination planet
if you're doing a demo mission there's no need to do that. You just need to demonstrate that the solar wind blows it around
>>sending them back to Earth
that costs MA$$ and power. You'll need a relatively big antenna to talk to earth. Oh and some attitude to control hardware too. Really the only goal should be just showing the damn thing works at all.

[Anonymous No.11806798]

>>11806769
Different anon here with an attempt at math. Definitely not a cubesat mission if you want battery power. Total engine power use is 10kW plus a few watts to rotate the coils times 24 hours of power for full "burn time" so about 25kWh. That's almost 100kg of Li-Ion batteries even at the high end of the energy density range. The reference mission from the article uses a 10kW solar array which is lighter but still unfolds to about 10 m^2 so you want something bigger than a Cubesat. These things really want big solar arrays or a reactor for useful payloads.

[Anonymous No.11806808]

>>11806798
but do ya really need 10 KW to demo it? You ain't going to another planet, just showing that solar wind blows it off course by the amount you expect it to.

[Anonymous No.11806821]

>>11806808
this

[Anonymous No.11806829]

>>11802914
>you can move 10000 kg of mass potentially to near light speed velocities with the power that seven microwave ovens draw
what the fuck

[Anonymous No.11806838]

>>11806829
As long as you have a giant fusion reactor doing all of the heavy lifting for "free".

[Anonymous No.11806861]

>>11806808
You need to have a fairly strong magnetic field to induce a rotating current in something as thin as solar wind.
>1kW current
>25kWh energy needed
>1m^2 of solar panels needed
I suppose at 10% power that could be doable with a 6U Cubesat if you're careful with solar panel geometry. Thrust power scales with field radius squared since it's a circular field, so 10% of the current through the same antenna should give you 1% of the thrust power, or 6kW of thrust for as long as you stay within ~1AU. That's actually still enough to drive a cubesat like a bat out of hell.


>>11806829
Solar wind velocity is like 0.1% lightspeed. To accelerate to relativistic speeds you need a multi gigawatt particle beam hammering the magnetic field. So >>11806838

[Anonymous No.11806950]

>>11806861
>1kW current

[Anonymous No.11807099]

>>11806950
It shouldn't take more than 1kW/h of voltage to provide enough magnetic torque energy.

[Anonymous No.11807105]

Ok, how to make this DIY

[Anonymous No.11807111]

>>11807099
>1kW/h of voltage
>Watts of voltage

[Anonymous No.11807122]

>>11807111
It's just a few amps of power bro.

[Anonymous No.11807141]

>>11807122
you need millions of ohms to power that tho

[Anonymous No.11807146]

>>11806861
I'm sorry to inform you current is measured in Amperes (A).

[Anonymous No.11807162]

>>11805770
>Yes.
No.
You only need two coils whose magnetic field has a phase difference of 90° in their alternating currents.

Also, this whole thing would be MORE scifi if it rotated, kek. Have none of you seen Event Horizon?

[Anonymous No.11807174]

>>11805746
>em drive
retard

[Anonymous No.11807199]

>>11807111
Watts per hour, Mr. Trips

[Anonymous No.11807204]

>>11807199
>watts per hour of voltage

[Anonymous No.11807206]

>>11807199
I think you meant wattage, not voltage

[Anonymous No.11807209]

>>11807105
>>11807162
The coil part is stupid easy. The hard part is getting it out past Earth's magnetosphere so it can actually work.

[Anonymous No.11807211]

>>11807204
Watts per hour of voltage expressed as magnetic torque energy. You following me yet?

>>11807206
I think you meant to check those digits.

[Anonymous No.11807247]

>>11807211
>Watts per hour of voltage
>Amperes per hour of resistance

[Anonymous No.11807275]

>>11807247
>FLOPS per orbit

[Anonymous No.11807291]

65 watts calculate for the amount of watt hours per amp volt

[Anonymous No.11807300]

>>11807211
>Watts per hour of voltage
You meant watts per hour of power
also checked

[Anonymous No.11807365]

How likely are the to be habitable planets on Proxima or Alpha Centauri?

[Anonymous No.11807374]

>>11807365
define habitable

[Anonymous No.11807381]

>>11807300
I'm check'n you too, how about I give you an hour of power?

>>11807365
0%

[Anonymous No.11807385]

>>11807374
Well ideally earth like with a breathable atmosphere. But I'll settle for planets with reasonable gravity, reasonable pressure, close enough to the sun for liquid surface water, not tidally locked, and no deadly radiation.

[Anonymous No.11807438]

>>11807365
100%

[Anonymous No.11807470]

>>11802795
People are still alive from a time when any human involvement in space was thought impossible. What's your problem?

[Anonymous No.11807482]

>>11802795
Is building rotating habitats actually anything more than an engineering effort though?

[Anonymous No.11807486]

>>11806829
What, you don't have 10^34 years of spare time to accelerate? Fucking pleb

[Anonymous No.11807498]

>>11807482
No. With Starship you really just need a big carrier craft with two sets of counter-rotating hubs to which pairs of Starships can attach. You could have 2x4 wheels so eight starships, and a plasma magnet sail could still get that big ass load of people there in two months if attached to the central structure..

[Anonymous No.11807918]

>>11801956
>Why is such a promising technology so under the radar?
the jews obviously

[Anonymous No.11808067]

>>11801868
because there are already better ways of spacetravel

[Anonymous No.11808070]

Traveling through large distances of space is sci fi fantasy bullshit.

[Anonymous No.11808332]

Space isn't even real.

[Anonymous No.11808927]

>>11808332
>implying you're even real
>implying this isn't all a simulation

[Anonymous No.11809095]

>>11806861
>1kW to run the drive
>24 hour period
>25kWh energy needed
>1m^2 of solar panels needed
>I suppose at 10% power that could be doable with a 6U Cubesat if you're careful with solar panel geometry. Thrust power scales with field radius squared since it's a circular field, so 10% of the current through the same antenna should give you 1% of the thrust power, or 6kW of thrust for as long as you stay within ~1AU. That's actually still enough to drive a cubesat like a bat out of hell.
Unit memes aside this is good news.

[Anonymous No.11809408]

Was just lurking and absorbing all this interesting information, but everything that is good needs to come to an end

[Anonymous No.11809561]

>>11809408
The stories and information posted here are artistic works of fiction and falsehood. Only a fool would take anything posted here as fact.

[Anonymous No.11810109]

What happens when this thing gets to the interstellar medium? Is there a "current" out there?

[Anonymous No.11810187]

>>11805360
>I'm personally going to start raising money to build one.
This sounds amazing anon. I'm not a rich man but if this gets going I promise to donate money.

It needs to happen. A test craft to prove this could work to get the ball rolling and the fat cats with the big pursestrings to pay attention.

[Anonymous No.11810189]

>>11810109
>What happens when this thing gets to the interstellar medium?
If the "spaceship" has already been accelerated, i'm guessing then it will just leave the solar system and keep its 0.2% c speed forever? Im also guessing as you leave the solar system there is less and less solar wind "density" or pressure, so if you were to start this thing outside of the solar system then it would take a lot of time to accelerate

[Anonymous No.11810191]

>>11810189
>so if you were to start this thing outside of the solar system then it would take a lot of time to accelerate
I'm also guessing you could compensate for that with an even bigger magnetic field, so if you need to accelerate faster then you power the motor with more energy

[Anonymous No.11810273]

>>11810189
For probes you don't care about hitting a destination, sure. If you want something to actually get anywhere then you'll have to hit it with a particles beam hooked up to a practically free energy machine and boost that fucker to several percent of c at least.
We've always known this shit was possible, but it's hardly a free lunch.

[Anonymous No.11810393]

Can a plasma magsail be added?

[Anonymous No.11810415]

>>11810393
>>>/reddit/

[Anonymous No.11810424]

>>11805283
the aerobrake capabilities are fake, it doesn't completely shield your craft from the heating

[Anonymous No.11810500]

>>11801929
>>11801956
Surely the US’s DoD knows of it? I hear those SR-72s can go really fast...

[Anonymous No.11810515]

>>11810415
speaking of reddit why haven't any science/space youtubers shilled this yet

[Anonymous No.11810659]

>>11810515
They aren't interested in borderline mundane shit that can actually work but is limited in application. Magnetic sails won't get humans to another system within a decade, so they don't care. Magsails have been featured in hard scifi books for decades though.

[Anonymous No.11810739]

>>11808067
citation needed I'm afraid

[Anonymous No.11810816]

>>11801956
>alcubierre drive
Impossible with currently available technology, unfortunately
>EM drive
never actually proven outside of margins of error except for in the measurements of the inventor
>solar sails
it's hard to make a thin sheet

[Anonymous No.11810877]

>>11810816
Is it possible the EM drives just aren’t getting enough power?

[Anonymous No.11810910]

>>11801868
I didn't quite understand what he said - how does he plan on slowing down a manned mission to mars?

[Anonymous No.11810924]

>>11810109
>What happens when this thing gets to the interstellar medium?
It's moving faster than the ISM so it slows down. That's why you shut it off when you hit the heliopause unless you have booster particle beams accelerating you further.

[Anonymous No.11810927]

>>11810910
Option 1: loop past a gas giant to slow down.
Option 2: build a particle cannon on Phobos or Deimos and hammer the field to slow down.
Option 3: only turn the field on briefly so your cruising speed is <50km/s and aerocapture

[Anonymous No.11811127]

It's frustrating for real life use, but the "can only accelerate in one direction" property is really interesting in a sci fi context. Imagine something like a Earth vs Mars colony war like is often the case in fiction and Mars thinks they have an advantage shooting down the gravity well, but then Earth packs out these bad boys and slaps them on missiles with cheap solar panels. Bam, you've got yourself a wave of 400km/s impactors that EXTERMINATUS the Martian surface.

The asymmetry is just really kino. You could have people sailing on the solar wind with small private aircraft and getting to distant planets within reasonable timespans without having to introduce torchships that are WMDs by their very nature. Also, Neptune is now prime real estate and its moons are blossoming colonies that rival those of the inner solar system, a situation you'd never see in any work of fiction without this tech.

[Anonymous No.11811145]

Pleb here. Is there no way to alter the angle of the sail to go against the solar wind the way a sailing ship can against the wind?

[Anonymous No.11811193]

>>11801868
>get to Mars in ONE WEEK
You left out the part where you need to have a superconducting antenna SIXTY METERS WIDE with 90 kiloamps running through. Needless to say, this will be very fucking expensive to build and cooling it will be an absolute nightmare. The 10cm version being discussed in this thread only gets you a single Newton of thrust and means this technology is currently only good for small probes and not much else.
t. apparently the only person in this thread who has actually read the article you linked

Jesus Christ, /sci/. Is it so hard to actually inform yourself for a second before discussing a concept over multiple days and 200 replies? This board never fails to disappoint.

[Anonymous No.11811496]

>>11810424
>the aerobrake capabilities are fake
>implying
Kirtley, David. "A Plasma Aerocapture and Entry System for Manned Missions and Planetary Deep Space Orbiters." (2018).
Shimazu, Akihisa, et al. "Cygnus Code Simulation of Magnetoshell Aerocapture and Entry System." APS Meeting Abstracts. 2017.
Kelly, Charles, and Akihisa Shimazu. "Revolutionizing Orbit Insertion with Active Magnetoshell Aerocapture."
Slough, John, David Kirtley, and Anthony Pancotti. "Plasma magnetoshell for aerobraking and aerocapture." 32nd International Electric Propulsion Conference. 2011.
>>11810659
But you can get to another system in decades with particle beams
>>11811193
>You left out the part where you need to have a superconducting antenna SIXTY METERS WIDE with 90 kiloamps running through. Needless to say, this will be very fucking expensive to build and cooling it will be an absolute nightmare. The 10cm version being discussed in this thread only gets you a single Newton of thrust and means this technology is currently only good for small probes and not much else.
Retard, this is discussed in the thread already. There's a lot of options between 10cm and 60m. Also, the technology is useful for radiation shielding and aerocapture.
>Coupling a more modest velocity of just 10’s of km/s with the function of a MAC, a craft could reach Mars in less than 2 months and aerobrake to reach orbit and even descend to the surface. All this without propellant and a very modest solar array for a power supply.

[Anonymous No.11811512]

>>11811145
Zubrin's version can, but that has kilometers of metal wire which sort of defeats the whole purpose of having a non physical sail. You can also make a version comprised of many magnetic fields see>>11802850
But it's best to have particle beams to travel back towards the sun. If you don't have them, then a power generating NTR gives you the best maneuverability throughout the solar system.
See >>11805360

[Anonymous No.11811537]

>>11811496
>There's a lot of options between 10cm and 60m
Oh yeah? Have you done the math? Show it to me. This things scales with radius, so you pretty much have to have large antennae if you want to move anything massive. Even just a ten meter wide coil would be insane, current superconductors have a critical current density in the 50kA/cm^2 range, so these coils have to be centimeters thick too. Which means it can't be built with high temperature ceramic superconductors, so you'll need metallic LTS. Have fun cooling those down to 10 Kelvin.

Please refute this. I'd love nothing more than to be able to cruise to Mars in a week within my lifetime.

[Anonymous No.11811547]

>>11802770
I doubt a superconducting wire exists that can hold 10kW without going critical

[Anonymous No.11811548]

>>11811127
>It's frustrating for real life use, but the "can only accelerate in one direction" property is really interesting in a sci fi context. Imagine something like a Earth vs Mars colony war like is often the case in fiction and Mars thinks they have an advantage shooting down the gravity well, but then Earth packs out these bad boys and slaps them on missiles with cheap solar panels. Bam, you've got yourself a wave of 400km/s impactors that EXTERMINATUS the Martian surface.
>The asymmetry is just really kino. You could have people sailing on the solar wind with small private aircraft and getting to distant planets within reasonable timespans without having to introduce torchships that are WMDs by their very nature. Also, Neptune is now prime real estate and its moons are blossoming colonies that rival those of the inner solar system, a situation you'd never see in any work of fiction without this tech.
Yes it's so sexy from a sci-fi world building perspective. Robert Zubrin called Saturn, Uranus and Neptune as "the Persian Gulf of the Solar System" because of the deuterium and helium 3. We will have Neptunian Helium 3 barons. We will have pirates occupying Mercury so that they have the "high ground" to harass ships from and be difficult to assail by the government. It's so kino.

[Anonymous No.11811596]

>>11803405
alpha centauri is very young and active, you wouldn’t want to be there.

[Anonymous No.11811621]

>>11811496
>you can get to another system in decades with particle beams
If by "decades" you mean nearly a century then sure.

[Anonymous No.11811654]

>>11811537
>>11811193
cont. because I find more and more bullshit >>11811496
The figure in the linked blogpost is obviously bunk. A magnetic deflection field with 1130km radius is not nearly enough to pull 0.2g. Solar wind has a radiation pressure of 1 to 6 nanoPascal, so for a 2MT spaceship you end up with... 0.0000003g (https://www.wolframalpha.com/input/?i=%281%2F2+*+1130km%29%5E2*pi*2+*+3nanonewton%2Fm%5E2+*1%2F%282megatonnes%29))
That's with the sixty meter wide superconductor antenna that has to be multiple centimeters thick. Listen fat, unless you're hiding high performance room-temperature superconductors somewhere, I think you're outta luck pal.

If I dare say so myself, I just BTFO this entire thread with basic arithmetic and fact-checking.

[Anonymous No.11811708]

>>11811654
See 21:38, in the video, when approaching Mars the magnetic field is approximately 100,000 km in radius. The talk is by Jeff Greason. He isn't a crank he was on the Augustine Commission.

[Anonymous No.11811716]

>>11811621
If by almost a century, you mean 20 years, then yes. Particle beams can get you to 0.2 c, they carry more momentum and are therefore much less power intensive than lasers for the same amount of acceleration.

[Anonymous No.11811816]

>Running an electric current in a circle produces magnetic force perpendicular to that circle’s plane
>Magnetic force mediates attraction and repulsion of magnets
>The Earth is a giant magnet
Does this make magnetism a valid exhaustless propulsion method, given a strong enough current within the aircraft?

[Anonymous No.11811818]

>>11811708
He may not be a crank, but I'd like to see some math from him, because those figures do not add up AT ALL. The original paper by Slough states a 100m antenna for a 10s of km wide plasma magnet field.

[Anonymous No.11811900]

>>11811816
Yes, in much the same way I could theoretically propel myself into orbit by pissing really hard and fast out of my dick.

[Anonymous No.11811917]

>>11811716
Accelerating anything big enough to carry a human for 20 years and the equipment to set up permanent shop at the destination will require legendary fuckloads of energy to get anywhere close to 0.2 c, even if you have zero losses. The technology and infrastructure to do this is within our means, but well beyond our desire to invest in.

[Anonymous No.11811925]

>>11811900
What if it turns out the government is hiding super advanced lightweight nuclear reactors? It could be like an aircraft carrier aircraft.

[Anonymous No.11811950]

>>11811917
>The technology and infrastructure to do this is within our means, but well beyond our desire to invest in.
Once Elon is a trillionaire things might change.

[Anonymous No.11811966]

>>11811950
Elon is going to be a mere billionaire cashlet for the rest of his life. He's been marked as dangerously based by the financial elite.

[Anonymous No.11812005]

>>11811966
>Elon is going to be a mere billionaire cashlet for the rest of his life. He's been marked as dangerously based by the financial elite.
It's not fair. Why are Elon's companies always one bad year away from going under but a fag like Bezos who has more money than Mansa Musa does fucking nothing with it other than build a giant dildo and try to patent things SpaceX already did.

[Anonymous No.11812045]

Does anyone know how the solar wind interacts in a binary system like Alpha Centauri AB? Would you be about to go anywhere in the system by riding the wind of the two stars?

[Anonymous No.11812078]

>>11811496
there's a 2020 article about the critical flaw in it, I'm not about to go find it right now because I've got to get to work

[Anonymous No.11812103]

>>11812078
About magnetic aerocapture? I'm not seeing anything? What's the title? If you were a true shitposter you wouldn't let something as trivial as work stop you.

[Anonymous No.11812104]

>>11812005
Gee, maybe it's because Bezos owns a company that supplies literally billions of people with consumer products.

[Anonymous No.11812106]

>>11812103
see you tonight, anon
I'll be back in twelve hours

[Anonymous No.11812251]

>>11810659
They actually do talk about ethereal meme proposals all the time though. I can find a ton of videos on alcubierre drives

[Anonymous No.11812255]

>>11811966
Elon setting up the first city on FUCKING MARS is going to make him immortal. Cash balances are fleeting.

[Anonymous No.11812636]

>>11811818
>>11811654
>>11811193
Can someone please BTFO this anon, otherwise stop fucking replying to this thread as this anon has proven its impractical for Mars missions.

[Anonymous No.11812984]

>>11812636
>otherwise stop fucking replying to this thread as this anon has proven its impractical for Mars missions
Because Mars missions is the only possible application, right.

[Anonymous No.11812989]

>>11811654
>>11812636
You're off by six orders of magnitude because you misread "megaton" instead of "metric ton." This is obvious from the video and was a basic transcription error by the article author. The reference 2500kg ship does in fact accelerate at 2.4m/s^2 when you fix the unit conversion errors. Scaling up to something else discussed in this thread, the acceleration for 1000 tons, or four full Starships in counter-rotating pairs plus a minimal central truss, is 0.006017m/s^2. That's less than 39 days to accelerate 1000 metric tons to 20km/s, and you can aerocapture at Mars to slow down.

[Anonymous No.11813067]

>>11812989
Also, if you increase the field radius you get non-linear returns on acceleration, which indicates that the 30m coil is at the low end of the efficiency scale for this technology. Increasing the 1AU plasma radius to 1500km gets you 0.0106m/s^2 for that 1000mt ship, which is pretty fucking spicy for sail propulsion. Considering hoop magsail designs need multiple kilometers of superconductor for just a 1km field radius with less depth, the plasma magnet is still a significant improvement in efficiency.

https://www.wolframalpha.com/input/?i=%281%2F2+*+1500km%29%5E2*pi*2+*+3nanonewton%2Fm%5E2+*1%2F%281kilotonne%29

[Anonymous No.11813081]

>>11811818
The original Slough paper assumed simple circular coils. Greason's design uses two pairs of saddle coils formed into a cylinder.

[Anonymous No.11813187]

>>11812984
Ah so you were BTFO, ok

[Anonymous No.11813209]

>>11813187
>you
Nah. I'm just pointing out a glaring flaw. Some anon did the real le btfo right after my post.

[Anonymous No.11813210]

>>11813209
...huh?

[Anonymous No.11813400]

>>11812989
Based, completely BTFOed

[Anonymous No.11813807]

>>11812103
https://ieeexplore.ieee.org/abstract/document/8741698
LMT seems convinced but idgaf either way, ceramics are fine

[Anonymous No.11813878]

>>11812989
>>11813067
You want to make it even larger? Jesus. It's much, much more efficient than a magsail, sure. That's very cool and has obvious applications for long-term missions and maybe station-keeping outside of Earth's magnetosphere. But considering you need tens of meters wide and centimeters thick superconducting coils - note how you're never defending this, just taking it as a given - for anything larger than a probe this thread totally misrepresents the tech! The small 10cm version discussed in this thread at length is still incredibly neat, it gets a 1 tonne probe to 11km/s within a month and to the 400km/s max in just 3 years.

But please don't try to represent this tech as something it's not. With our current knowledge of material science, this thing won't propel a human anywhere for a long time. The superconductors you need are just too large. You can try to jam up the current going through them, but I suspect that gives you disminishing returns on overall plasma magnet bubble size and you run into critical current density issues even faster.

[Anonymous No.11813905]

>>11812989
so what about the crucial part you sneakily ignored? Where’s the superconductors for it?

[Anonymous No.11813912]

>>11813905
dude just get the wires in the freezer

[Anonymous No.11814794]

>>11813912
>dude just get the wires in the freezer
This but unironically. Just shade the spacecraft, install radiators.

[Anonymous No.11814860]

>>11814794
Not that easy. This has been discussed in the thread already.

[Anonymous No.11814932]

>>11801951
to generate an electric field big enough to move the space station and it's nuclear power plant it would have to be bigger than all other launched spacecraft combined, then once it got there is it disposable or something? what a waste

[Anonymous No.11814961]

>>11813905
>>11813912
>>11814860
STFU all "superconductors are impossible" doomers. Even the meme James Webb can cool down to 7 Kelvin.
https://www.jwst.nasa.gov/content/about/innovations/cryocooler.html
>Passive Cooling
>Three of Webb's four scientific instruments "see" both the reddest of visible light as well as near-infrared light (light with wavelengths from 0.6 microns to 5 microns). These instruments have detectors formulated with Mercury-Cadium-Telluride (HgCdTe), which work ideally for Webb at 37 kelvin. We can get them this cold in space "passively," simply by virtue of Webb's design, which includes a tennis court-sized sunshield.
>Active Cooling
>However, Webb's fourth scientific instrument, the Mid-infrared Instrument, or MIRI, "sees" mid-infrared (MIR) light at wavelengths from 5 to 28 microns. By necessity MIRI's detectors are a different formulation (Arsenic-doped Silicon (Si:As)), which need to be at a temperature of less than 7 kelvin to operate properly. This temperature is not possible on Webb by passive means alone, so Webb carries a "cryocooler" that is dedicated to cooling MIRI's detectors.

[Anonymous No.11815255]

>>11813878
>>11813905
Solid cooling is adequate for magsail wires. Designs have been known since 1990. Cutting the length of superconducting wire required from Πr2 to a tiny fraction of r makes it actually usable with existing superconductors like YBCO.

[Anonymous No.11815807]

>>11812989
>That's less than 39 days to accelerate 1000 metric tons to 20km/s
So in other words using this thing for asteroid capture might actually be viable?

[Anonymous No.11815824]

>>11814961
The JWST is not 60 meters wide.

[Anonymous No.11815833]

>>11815824
Even assuming the cryocooler is ten times the mass of the coils and uses twice the energy you still get a ludicrous payload fraction compared to chemical rockets.

[Anonymous No.11815958]

>>11801868
Why couldn't you just have many of them arranged in a line and have them phased so that "sail" can be pushed forward or backward?
You could amplify the thrust or the braking this way and also push off of stationary clouds of charged particles.

[Anonymous No.11816515]

>>11815958
That's been discussed elsewhere:
>>11802850
It's possible, and if you scaled it up enough you could tack into the wind and move towards the sun, but that's a lot more mass and a much more complex setup (dozens of 10km+ tether wires carrying thousands of amps), so people tend to focus on using the single sail and then some other propulsion system.

[Anonymous No.11816666]

>>11803099
>>11803113
>>11803377
>>11803405

This is like watching a blind man having a conversation with a dog thinking it's his wife

[Anonymous No.11817499]

>>11816666
Checked. Half this thread is incomprehensible.

[Anonymous No.11817503]

>>11801986
>>11801976
we should test this