Air Breathing Ion Thrusters & Low Orbit Satellites
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- Опубліковано 24 бер 2018
- Lower orbits are desirable for some spacecraft, but the Earth's atmosphere doesn't give spacecraft below 300km a long life. However ESA scientists recently demonstrated an electrical ramjet that could make low orbits viable for long term spacecraft.
- Наука та технологія
Yeah the moment I heard oxygen, nitrogen and ion in the same sentence, I thought to my self "that may be problematic"
They're going to have to be lined with a high-temperature non-reactive substance. I'm going to spitball and say a Hafnium/Gold alloy.
Explosion or dinitrogen tetroxide?
They have all that mass to play with that normally would be reaction mass. I think they will find a solution, even if it will wight a few kg.
2 much science
@@davidturpin9135 Do you need a high-temperature material? Sure, the plasma is at a high temperature, but that doesn't mean solids in contact with it are necessarily even too hot to touch with your finger, due to heat capacity and conductivity reasons. Maybe relatively mundane platinum, gold, or graphite electrodes would work.
"So, yes, there are a few old Soviet nuclear reactors floating in space"
Excuse me
Even better, they leaked coolant, liquid Sodium/Potassium coolant. Which has solidified into metal drops, like shotgun pellets, at orbital speeds.
The problem with sodium or potassium droplets is that they would have a very tiny radar signature, and so no warning can be given before they hit something.
We currently have launched 40 RTGs and 30 Fission Reactors into space. According to Wikipedia 13 nuclear powered spacecraft are still in earth orbit. Cosmos 1402 re-entered 1983 over the South Atlantic and Cosmos 954 re-entered 1978 over Canada. Apollo 13 also used a RTG, which re-entered with the Lunar Module 1970 and landed somewhere in the Tonga Trench in the Pacific Ocean. Also I heard one US nuclear powered satellite exploded on launch, but I don't have a source for that.
en.wikipedia.org/wiki/Nuclear_power_in_space ("Table")
en.wikipedia.org/wiki/Apollo_13 ("Spacecraft location")
But what if it hits a metal wall and showers the internal volume with shrapnel, or strikes something solid and converts all of its kinetic energy into a fireball?
Don’t worry, it’ll be fine. It’s not like a nuke is gonna drop from orbit onto your head.
Wait, what’s that outside-
They have a few of those Keyhole satellites in the Wright-Patterson Air Force Museum. They even have cutaways and the film capsules to look at. If there is ONE museum to see in your lifetime this is the one to go to.
I would counter with the Smithsonian Air and Space Museum as the one museum to see in your lifetime.
@@emmanotsostrong Why not see both? If you’re interested in military aircraft then the Air Force museum is the best.
Designing air intakes for super sonic speeds it difficult enough... air intake at orbital speed... wow! :-)
ya.. we still dont as far as we know have an operating Aurora Scramjet (ramjet.. somethingelsMjet , whatever) and theyve been working on that since the 70's or 80s.
there isn't that much air at orbital altitudes. and definitely not enough to fuck something up at the altitude this would be used at.
A lowest ceiling is also known as a floor, Scott.
or deck
you mean bottom...
Or *SPLAT....*
One man's ceiling is another man's floor.
In zero G, isn't essentially everything a wall? Just space thoughts...
Also if you can get the efficiency up so you for example only need to use half of the gathered air to maintain altitude, then you could store the rest and periodically boost the orbit up to put it in a depot. This could save on mass needed to be launched from the surface.
I did some computations about this once. It would be very slow to accumulate significant amounts of air. One limiting factor is cooling: slowing down the incoming air produces heat. That heat has to be radiated away.
If you could use hydrogen brought from Earth to make hydrazine and nitrogen tetraoxide you could have a gain on the order of 20 to 1. So a rocket carrying 100 tons to orbit could potentially fuel a storable propellant rocket with 2000 tons of propellant. This would easily launch hundreds of tons towards Mars or a similar interplanetary destination. A similar system could be installed at Mars and Venus, using CO2 to make CO and O2, and with hydrogen and nuclear thermal rockets the outer planets become refueling hotspots.
Sounds kinda like a Bussard ramjet, minus the fusion of course.
A lame Bussard, basically
A Lamard? A Lamebuss? A Blame?
Bussard Ramjets , as it turns out, will never have a greater efficiency than "Flashlight Drives"
@@mihailazar2487 I've heard of torch drive but not of its American counterpart.
The second satellite image at 1:46 is actually the Hungarian city Szeged!
Sir your videos are truly fascinating. You are teaching me things i had no idea about... thank you.
Never thought air breathing ion thrusters were possible. Great video, learned something new.
6:24
Please consider doing an ion drive 101 video. That seems like a very interesting subject to skim through. I did a search for "Scott Manley Ion," and noticed the 'Why Ion Drives use Xenon' video but I didn't see anything more broad about the different types of ion drives.
Thanks for the upload,
-Jake
I am glad I found this video. I have heard of 'ion engines', but did not know there was such a thing as an 'air breathing ion thruster'.
_So its basically a Electric Jet engine_
well yeah but no. Because you need no fuel. Or rather the fuel u use does not add weight to ur system.
@@durschfalltv7505💃💃
I just saw this episode Scott that it is just really interesting!!
These kind of videos are my favourite from you
"Ladies and gentlemen, we will be cruising at an altitude of 825,000 feet and our arrival time is in 2 years. Thank you for flying Ion Airlines."
So could a satellite dip into Jupiter or Venus atmosphere and collect "fuel" for longer missions using this method?
For that We should produce Big Engines If a Satellite Orbits near Jupiter it needs up to 50+/-Km/sec speed velocity If anything went wrong that satellite could die easily in Jupiters atmosphere due to its Giant size and Giant Gravitational Force but Near Venus it (Satellite) can Work as near the Earth! :)
I think it would be much harder than on Earth because you still need electrical ppower for that.
Jan Czech There is a strong magnetic field surrounding Jupiter, so a space probe can't run for a long period of time. However it should be possible on Venus or Mars. In fact Mars' atmosphere is thiner than Earth's one, so a probe could run on a lower orbit
Jupiter: extreme radiation, very low solar flux, orbital speed comparable to if not exceeding exhaust velocity (altough that's hydrogen... there should be calculations somewhere). Not really feasible
Venus: more solar power than on Earth, gravity is a bit less... Might work
I'm thinking about something else: that ion thruster needs a lot of power which is increasingly more difficult to find the further you go from Sun. There is very little sunlight to power solar panels and reactors are a no-go. This idea might work on Venus but imo not on Jupiter and further.
i already did that in KSP in 2014 ( i had no internet for 10 years and a friend dropped a copy of that game! coolest game ever!) when you put a air scoop and scoop air, you use a compressor to compact it for later use. you have 2 tanks, 1 for xenon that is more powerful, one empty that you fill up over time in a few passes.
you need to do egg shaped orbits and only skim the atmosphere so you have very little drag, so before when you enter, you use a bit of gas, and when exiting you use also a bit, this way the apogee remains a bit the same, AND at the apogee you set the lower point higher correcting both sides.
if the drag is low enough the speed will feed the collector alone and the apogee makes you not need much fuel to stop making passes in the atmosphere! just that KSP's atmosphere is hard ended at 70 km so... i don't know how well in an analog world this would go ;P i usually made passes around the 65 to 68 km mark to fill it up.
would be nice if i could buy the real game tho... maybe one day when we actually HAVE money... Windows, Games and other things... the only real things i have are friends ;P
I really enjoy videos like these.
When you mentioned the day/night issue I was thinking, "But twelve hours later, the night side would be the day side anyway." Then I gave it some better thinking and realized that the relevant interval is more on the order of two thousand hours than twelve hours.
Boy!!!! I can remember when the coverage map shown at 1:33 was really a very high secret!
This was very interesting, thank you. And yes, oxygen is very corrosive.
Jack Vernian only if metal isn't oxidised
love you scott huge fan keep it up :)
this is very cool, for some reason its very cool to me imagining things circling earth in artificial orbits just skimming the atmosphere
The glow on those engines reminds me of something from Homeworld or something. So cool.
I know what we'll do! We'll make the thruster walls out of solidified noble gasses!
What? We need conductors?
If only there was some non-contact way to energize the gasses, you know, some kind of variable specific impulse microwave rocket.
Thats not what it stands for? Oh well. It was close.
I'm pretty sure Vasimir works with plasma not microwaves
Great video and information
Small question. Wouldn't the perigee drop on the dark side when it is unable to thrust?
Thanks for doing a video on this, as it is an interesting proposal. I'm curious on their graphs what attitudes they are talking about. Very interesting how much stronger their Thrust/Drag is at lower altitudes. I wonder if that is just because it's easier to capture when air behaves more like a fluid.
The normalized/corrected lines are almost all *way* below 1.0 Thrust/Drag. Only the first red line seems to generate appreciable sustainability.
Looking forward to someone porting this sort of engine to KSP.
If anyone is interested, you can see an ion thruster lift its power supply from the ground, just click on the channel icon to the left. It is thoroughly verified that is works, and patented specifically for carrying its power supply using ions.
Thanks for this video, really interesting! Reading the title made me say "uhh...huh?" And the video made me say "Oh. Ahh...huh!" Super cool idea that I have never even considered!
I love how in the cold war basically they just put nuclear for any energy problem
Scott Manley this is also the key technology required for Propulsive Fluid Accumulators. If you have a satellite that can hang out in Very Low Earth Orbit for long enough, you can collect some of the atmospheric gasses present and store them for later transfer to a fuel depot in a higher orbit.
The only missing requirements for this were an airbreathing electric thruster, an intake design for it, and a system for orbital fuel transfer between spacecraft... We already have SEVERAL ways to provide the electric power- nuclear reactors, solar panels (require collecting at significantly higher altitudes, where the panels generate relatively more power for their drag), or Beamed Power (microwaves from the ground or lasers from higher orbits- rectenna technologies to convert microwaves back to electricity have been around more than 50 years, and were used to fly a toy electric helicopter in 1969... Lasers are converted back by specialized solar panels optimized for that particular wavelength, and operate better over long distances than microwaves- though do not penetrate as well through the atmosphere...) Collecting the gasses can be performed by use of an intermediate tank, like you described, and siphoning off a portion of the collected gasses for storage rather than propulsion. Gasses intended for storage get cooled down to cryogenic temperatures (takes a lot of power per kg of gasses- but these systems would be operating on *tiny* gas flow-rates, or very intermittently on larger amounts in intermediate gas storage tanks) and then siphoned to long-term storage tanks.
The power requirements for such a systems are large per kg collected, and most first-generation solar-powered systems are estimated would only collect a few hundred kg to a single metric ton of gasses per year (note that most systems propose separating the Oxygen from the other gasses and only storing it, as the most power-intensive step is cryogenically compressing/cooling the collected gasses and Oxygen is considered the most useful gas in LEO for its utility in chemical rocket engines...) But if the system worked at all, that would be justification for building larger, more efficient systems that could collect greater quantities of gasses.
The ultimate goal of such a system would be collection of surplus Liquid Oxygen for storage in a fuel depot in a much higher orbit, which could then be used to refuel spacecraft headed beyond LEO (if you're going to Mars, for instance, you only launch with enough Liquid Hydrogen to make the transfer-burn there, but no LOX for it. You pick up the LOX from the depot and save yourself quite a bit of launch-mass...)
Also, the component technologies, like refinement/demonstration of Beamed Power and fuel-transfer systems would also be useful for countless other mission profiles, from contracting out fuel-launches to an orbital fuel-depot (let's see who can get a ton of Liquid Hydrogen to this fuel depot cheapest... Now opening bidding...) to eventually developing Beamed Power launch-systems straight from the ground (which are capable of attaining much better TWR's and ISP than conventional chemical rockets, and can potentially use pure Hydrogen to launch...) and orbital Beamed Power systems like Project Starshot (basically accelerating a tiny probe to a significant fraction of the speed of light using lasers on a light-sail, with the objective of sending a miniscule probe to a nearby star...)
Love your vids so guud thanks Scott
Good video!
6:23 what what? What are all these thrusters? TEACH ME SCOTT MANLEY, I WANT TO FLY SAFE
I seen crygenic cooling of air at low vacuum pressures. I´m not sure if that is possible in that low of a atmosphere. But i se no problem with it.
About a tank. We ar talking really a few grams of air, the tank can be rather tiny.
With a really low orbit you would get... hmm don´t remember exactly, but about 20 minutes of day, and about 20 minutes of night.
The intensity of the sun is about 1367W/m^2. You would get about 1/4 of active sun on the panels. That is for 40 minut orbit you get 10 minutes of active sun (if the panel is inline with the orbit and orthogonal to the sun)
With a 3 junction cell (they are rather expensive but i se no reason not to use them in this applikation) you get about 40% of efficency. So the panels should produce about 550w/m^2 For 10 minutes that would give you 91wh of energy. Using LTO battery (pretty much the only kind that can charge that fast). That would give you just under 1 kg of battery needed. With LFP you could get away with 770 gram of battery per m^2 panel
Of cause, if you assume that the engine is perfectly made to have a prefect thrust they would use 137 watts for 550w of solar panels. That would give you a maximum charge rate of 413w/m^2 solar. That would also decrease the amount of battery needed with a equivalent amount so you would need about 68wh/m^2 solar in turn lowering the amount of battery needed to about 750 gram for LTO or about 670 gram for LFP.
I would probobly ad a additional NCA battery for emergency power of something failed.
One issue with this solution is that even LTO have a very long cycle span, about 10 000, with 36 cycles a day, the battery would wear out in 9 month. Super capacitor is probobly the only way to go for this kind of aplication. The best one (avalible) is about 20wh/kg. So that would be about 3½ kg of capacitor per m^2 panel. They handle at least 100 000 cycles. So that would give you at least 7 years... probobly a bit more.
matsv201 -- A very low orbit is still about 85 minutes long, so energy storage would last longer than you calculated, but also have to store more. And cycle life can usually be extended even more with precise thermal control.
" A very low orbit is still about 85 minutes long, so energy storage "
Right. i couldn´t find the right orbital data when i wrote it.. so i just guessed.
"so energy storage would last longer than you calculated, but also have to store more"
Yes the batteries would last twice as long, but also need to be twice as heavy. Of cause, that would make it more tollrable to lower power batteries. Still a NMC battery would still be to slow.
"And cycle life can usually be extended even more with precise thermal control."
Not really. The lab testing is done under precise controlled situation. Rather the opposite is true. If you don´t control the temperature the life time is decreased.
You can improve the life time by not full charge or disscharge a battery. Going from 20-100 charge to 40-80 will increase your battery life span by 30%. But going from 40-80 to 50-60 till in steed decrease it.
Of cause, if you want the satellit to be upp there more than a year or so. Batteries is pretty much out of the question. The only battery i know that can handle even large number of cycle is the Ni-H battery. But they have a problem that they charge pretty slowly.
It seems to me that the most logical way to protect the innards of the engine would simply be to apply a very thin coating of some highly non-reactive metal, such as gold or platinum. Since we're just talking about a few grams here, weight isn't significant. The real question is whether it's a problem if the inside surface of the engine is conductive. Remember that the ions and stripped electrons want to be back together, and if there's a conductive path, they'll use it. And electrical flow can be restricted to the surface coat just by putting a non-conductive layer beneath it, but it will still traverse the surface and give it a charge.
Is there anyone here familiar enough with the workings of ion engines to say whether this sort of thing is a problem at all?
I've been thinking that the cross section area of a space vehicle could be a cone at the bow to collect what normally would just bounce off of it. Especially useful in interstellar space. Either use it for fuel or mass to be ejected out the back.
There is no prase as calming as "old sovjet reactors"...
Interesting concept honestly.
This is awesome!! could also be used for communication and internet satellites.
Lower latency and better signal strength and so forth...
This was a really fascinating video! Thank you for sharing. I had no idea old Russian nuclear sats were orbiting the earyh
Few years ago we was thinking about atmospheric nitrogen orbital tug. For SSO orbits. It had to fly on electric propulsion. (microwave heated gas and magnetic nozzle) It was on solar panels (on sso sun is always from side, so you can place them along the craft so no big drag), it has heat radiator too. Idea was it use atmosphere nitrogen to propulsion and collect it to the tank also. so it can change orbital height in wide range. So, it was launched on 110 km orbit collect nitrogen, cooled it to liquid... yes I know lot of problems mostly because power. (only for cooling nitrogen about 2 kWth per kg...
6:50 I believe its more like a ram scoop. The initial orbital launch will provide that speed.
Need this video needs to be updated
I've always wondered how air molecules hitting the spacecraft at orbital speeds don't do damage over time, even at a microscopic scale. It would seem that they would impart a significant amount of energy onto the molecules of the spacecraft which they strike, just like alpha or beta particles.
They do 'damage' the orbit, the ISS has to do a periodical booster burn to maintain it's orbit about once a month
Michael Farrell I know it degrades the orbit, I'm asking about the surface materials of the craft. Isn't it essentially sandblasting the surface?
Ever wondered what causes re-entry heating -.-
Special EDy one molecule doesn't have enough mass to damage an object. The mass of a O2 molecule is 5*10^-26 kg. Its kinetic energy in low orbit is about 3*10^-18J.
In fact the molecules of the atmosphere near the ground fly at more than 1km/s, which is really fast. But you don't feel anything because they are extremely light.
Special EDy remember that for each particle the energy of the collision is equal to the mass of the particle times the velocity squared. The particle masses are in the order of nano-grams so even at orbital velocities the impact energy is extremely small. Not enough to do significant damage to a spacecraft. Now bigger, dust sized particles like micrometeorites are a problem.
Thank you for this video!
Could you PLEASE post the link to the sources of those diagrams for the intake/collector?
Thanks.
I've been hoping that it would be possible for ion drives to use oxygen as a propellant, because oxygen is ubiquitous. Ordinary rocks are full of oxygen, whether they're moon rocks, Mars rocks, or rocks from rocky asteroids.
I'm wondering - provided this concept works, could it be used to raise the apogeum of a satelite to some significant height ? Or would the perigeum speed increase (if I understand things correctly) quickly zero any benefits due to more drag ?
Very interesting video
Bussard collectors and impulse engines... damn it... Gene was an alien posing as an Earthling. ;)
Or perhaps a traveller from the future?
A planet at Peace, no more poverty, everyone worked and was happy. You just figured that out? :-)
escarfangorn I‘m sure the idea for Bussard ramjets is older than Star Trek
I was getting frustrated that I couldn't understand the concept of the ion thruster, but then I realised that it really was rocket science
Could the air intake ion thruster be used in a gravity measuring satellite? The mass flow rate is highly variable and with the varying drag and thrust, that would introduce many more variables to the system making it much more difficult to precisely measure the gravity to the level they want.
Aaah. Quality content.
It's great theyre working on this because
A: we need to develop atmospheric 'scoops' that can make atmospheric dives to collect gasses for fuels. This will be a BIG advance in space travel technology. Instead of launching fuel at 1000s or 10s of 1000s a pound into space you have spacecraft whos only job is to collect gasses and dump them at a storeage facily
b: Most of the best interstellar ideas ive scene involve nuclear engines or ion drives that collect hydrogen in space as a propellant source for an electrical engine. Youre not going to launch some interstellar craft waying millions of tons into interstellar space by carrying all of its fuel with it. And as far as i know we arent even at the beginning of thinking about producing antimatter much less storing it
It's a good idea to avoid decay. EM drive may do that if it really worked.
I think if anything the fact that we will have to deal with the long term corrosive effects of oxygen on the spacecraft is a good thing. It means that we are able to keep a satellite in VLEO for long enough that it becomes an issue.
First place I heard about this air breathing engine, thanks! However Xenon being an inert noble gas isn't really the reason it is used, only a useful property of the gas. More useful properties are the low ionisation energies of Xenon and and it's high atomic mass, allowing higher thrust per unit mass and per kW power. It's also quite dense. The earliest space ion thrusters used Mercury which has similarly low ionisation energies, a higher atomic mass and very high density but has some horrendous reactions with metals. Some ion thruster concepts have even used Caesium despite being highly reactive!
YeHahh n tnx for the info but he already made a video on this exactly the info u said
If they suceed and also have margin to enable orbital raising, this engine might actually enable JP Aerospace's Airship to orbit concept to suceed as well.
hello, very interesting video, made me think of a few questions if you don't mind.
1. Instead of xenon is there any solids that would flake off, or be made to flake off that might work for a ion drive?
2. Where might i find an approximate value of a ion drive? dozens of videos and I have no idea what it costs to make one.. or who for that matter makes them?
3. I believe Nasa wanted to use a 50w Ion drive (or something like that) did they ever design and/or build one? Would it just be a matter of building up bigger power sources or would they need a significantly bigger ion engine to get the higher thrust?
appreciate if you can, or at least try, to answer my questions if not thats ok to.. enjoy your videos. Thankyou sir.
Is it possible that collecting the particles reduces drag by half, because otherwise it seems like a fully elastic push?
How does a guy that started a channel about video games know so much cutting edge engineering and spec details !?!
Hey Scott, could you do an episode on how steam-powered rockets work (like the piddly one Mad Mike Hughes just launched)?
I envision low Earth orbit ion-powered liners flying passengers on 1 week and 1 month vacations. Think cruise ships. Think the sights with binoculars and telescopes of the world from low orbit. It would never get boring.
I wonder if we worked out the kink in the idea and made practical and use this on a regular basis, I wonder if;
1. Would it create or interfere with the ionosphere?
2. Would it affect the ozone layer?
One sentence "Corona Programm" makes UA-cam Push this Video in 2020 🤔
Corona originally comes from the solar lava "spikes" that you can see at a solar eclipse and from there does the name come from
@@zeroiq3243 corona actually means crown in Latin so both the virus and the solar features derive their name from there.
I really want to hear your thoughts on Mike Hughes. 😝
3:00 - there are nuclear reactors in graveyard orbit?
You know, it's such a good idea for a space-sym game. Where one of the "quest" or "locations" would be scanning around the graveyard, finding and scrapping useful stuff from long dead sattelites.
Since it is coated in solar panels and flying low, I wonder if it will cause flares like the Iridium satellites.
nitehawk86 it will if the angle is right.
I'd always assumed that at these altitudes H, H2 and He would be the dominant available particles. Also surprised that 40% loss of incoming gas is a good result. It seems like a long shallow funnel collector with some kind of one way surface, a bit like shark skin, would achieve a much better yield than that.
What is the impact to the atmosphere at high altitudes from freeing these particles from natural settlement and the constant lateral thrust? Would this be carving out big areas of upper atmosphere with its thrust? How much volume would you say per orbit could be ejected or blown away?
Scott I was literally thinking about this exact idea, how did you read my mind
YASSSS Great Video!
this definitely needs a follow up video, with more details, more explanations
Waiting for papers I can read
Hello Scott! I've got a quest(ion) for you. Could you maybe show us the two alternative concepts of traveling to he moon? As far as I know at the very begining scienist considered making a single stage rocket that would travel to the moon and back. I was HUGE and singe stage. The second concept was to build a spaceship on the orbit via few spaceflights and docking and then send it to the moon. As we already know that was not the way we as humans did it but it would be iteresting to see you simulate those alternative concept in KSP. Great Chanel content! Sound.
Robert Zubrin has always been a fan of Moon direct, as well as Mars direct. It'll likely take some moon side infrastructure. We'll see how things play out.
you should add a list of the mods you use in your game in the description.
Thank you Sir.
i once build a station in a 70 km orbit, it worked for some time but every once in a while due to its length the far end of the station hit the upper most atmosphere slowing it down without fuel to correct this it eventually burned up.
i now orbit craft at 7100m in KSP
At what lowest sealing this can give postitive thrust-drag is one interesting question.
The other one is the pure opposite: Can it work as high as the spacestation(and beyond) and lift the orbit of satelites, spacestations, supply-ships a.s.o.?
It seems to be quite similar in design to the Goce satellite, that was covered in solar panels with fins to help aerodynamics keeping the correct orientation and its ion thruster was constantly active supplied by 1.3kw of solar energy from 9 m2 solar panels (with the craft capable of a peak energy output of 1.6kw) which also powered heating, communication and instruments. The 40kg of Xenon was expected to produce a lifetime of 20 months but it actually operated for 55 months with most of the fuel consumed within the last 11 months of its life. (Anyone want to calculate the MPG the 40kg of Xenon achieved?)
The ion thrusters are having the magnetic trap (basically lined up strong magnets) counteracting or disallowing the ions to touch the thruster's walls.
Otherwise, the ions of Xenon gas that were transformed into the plasma like gas would burn through the walls long ago.
Thank you.
Turbomolecular pump stages should increase collection efficiancy
Exciting stuff! It would be amazing if it were possible to fly satellites as such low altitudes indefinitely!
What if you had a small nuclear reactor, that had the energy to propel it's reaction mass to an exhaust velocity of near light speed? So it would gather up some air molecules from the intake, run them around a particle accelerator, and then eject them.
Penny Lane Even if the engine doesn't get damaged, there's still the problem of battery degradation.
i'm pretty sure nuclear ramjets exist, they could fly 20+ years at mach 5 in atmosphere. but that's classified
I am very sure that this is bullshit. In fact a lot of companies are working on (s)ramjets, but they continue to fail. The excessive heating at Mach 5+-speeds melts every ([s]ram-)jet engine so far. Boeing archived a 9 minute flight with Mach 5 until the engine failed and the craft was destroyed. The most capable aircraft seems to be from China, but little is known so far. It is speculated that they use a rocket to propel the aircraft into the hight and speed which is needed for the scramjet-engine.
@Special EDy: When you want a spacecraft to get near light speed you would need large amounts of energy (and fuel). I dont think we can do this with our current technology. Maybe with fusion reactors at some point.
Iustinian Constantinescu, yeah, I know, damn batteries...
The thought of air molecules bouncing off the intake and getting away is kinda eerie
Think of “viscosity”. High mean free path means low viscosity.
"getting away" as in leaving with enough energy to be carried away by our stars radiation?
Imagine wanting to breathe but all the air just bounces off your mouth and flies away
@@GewelReal Lol I laughed way too much about this.
Two years on Scott - any update on this technology?
I had a proffesor who said that he worked on using the radar maped hight of the ocean to map the topography. He said that his project was shut down by the Americans because they discovered you could track a submersed submarine by tracking its wake.
thats funny
Professors say a lot of dumb shit sometimes.
So why not employing him then to work on a top secret project to detect russian and chinese submarines?
Basicaly the system was supposed to allow the team to map the seabead via satalite. The idea was that variations in the seafloor would create local gravity anomolies. These would alter the average hight of the sea level, which you would use radar telemetary to find. A moving body in water will leave a wake. Apparetly the system was sensative enough to pick up the subs wake; not that you would be able to see it from the surface or be able to precicely pinpoint the sub.
Being a brittish research student he was probobly shut out/down because he wasnt an American nor privy to secret information. Seems they didnt want anyone but their own people in on his when it came to light and who can blame them. Even if it came to nothing it is an interesting line of inquary with clear strategic value. Why share if your dont have to?
Joseph Stalin We would have killed him. Without a doubt.
Could this function as a high efficiency upper stage? Assuming some stored propellant for the final part, a satellite could be left in a very low orbit & climb to a proper one.
7:18 why would firing on the night side be necessary? I think that only applies if the engine firing direction is assumed to be very constrained?
Oh wow! This is a thing? I've always wanted to build exactly this. I'll be following this closely. I want to modify a vasimr engine to do this.
This is genious!
I wonder whether it will also work higher up where hydrogen and helium are the dominant gasses. They'd probably need a bigger collector on the front but it could be covered in solar panels so not much increase in mass.
With a highly elliptical orbit could you go very low through the much more dense atmosphere, but still have enough chooch to get back out to the moons gravity well and regain some velocity? It seems like there is a lot of discussion about fuel scooping and similar, but if you pick up enough fuel actually fill up a combustion rocket (or even a fraction of the fuel needed for a fairly large rocket) it just seems like you would need way more power output than an ion thruster setup really gives you. I don't know much about orbital mechanics, but rockets take a lot of fuel so anything that is going to refuel them is going to be big and heavy and hard to accelerate without taking advantage of some gravity help. If the idea really is to bounce up and down over and over again using ion thrusters to power the bounce, would you be better off leaving the big tank in a high orbit and dropping off little bits of fuel each bounce, or keeping the tank with you to keep momentum as you skimmed through the denser parts? Great video! Kind of imagining Starship screaming past earth in a fireball to refuel before heading to mars... It might even work if you got the altitude right and used the precoolers from the SABRE engine to liquefy the atmosphere.
Could something similar be done with the solar wind? Collecting it using electrostatic collectors. And electrically accelerating it back out? Youd have to get going pretty fast to get it to start if you are headed outbound unless there is a way to guide it in a U shape...
The thumbnail has a cool optical illusion
So ESA just built the first in orbit fuel scoop. Nice!
Is anyone else hoping this gets implemented into KSP, would love to be able to gather some science by flying low orbit satellites around Kerbin on this new style of ion thrusters.
Bussard ramjets when?
Would it be possible to have an aircraft which uses this as its primary form of propulsion?