@@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.
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.
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.
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
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.
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?
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.
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 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'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.
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.
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.
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.
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...)
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! :)
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.
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 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.
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?
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.
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.
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.
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...
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!
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
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.
for the US's part thats because other than Musk we dont really have any launch capability (and his less capable competitors).. because obama effectively ended our space program. Which imho resulted from the boondoggle we called the shuttle. You can be sure the russians, europeans, japanese, indians et al are continuing development howevr. It's just that our press tends to only cover it's own nations space programs for the most part
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.
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.
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.
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.
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.
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.
3:00 The soviet unions nuclear satellites are an interesting story. When the reactor core was ejected from the satellite and boosted to a higher orbit, the mechanism obviously broke the coolant lines. The sodium potassium used formed small droplets which now orbit in a bunch of places between the graveyard orbit and LEO. Quite an annoying form of space debris
Scott Manley -- There are a few questions/comments this concept has "re-ignited" ;) about Bussard Ramjets. To go faster and faster and finally get close to lightspeed, using only in-situ propellant? Never happen, that is a juvenile fantasy. Bussard Ramjet is still a jet, so it has Inlet Drag, which must be overcome by exhaust force and velocity higher than inlet drag and velocity. But fusion can only make exhaust velocity of about 5% of c. Still, *a modified version can work very easily* at a wide range of speeds, without needing any kind of nuclear power, or chemical combustion. The trick is to gather in the oncoming matter, add reaction mass to it, then expand it gradually away, along and behind the craft. Same energy into more mass makes a net thrust. But you have to bring reaction mass along, and get some initial velocity by other means. For a starship, even sand will do for the reaction mass. In the atmosphere, working towards orbit, you need hydrogen... not to burn inside engines, but to have lower average molecular weight in the exhaust than in the oncoming air it gets mixed with. It will burn, but mostly far behind the craft, where it cannot produce thrust. This little-known trick of _adding inert mass to make net thrust_ is worthy of a video, imho.
I’ve mentioned inert mass injection a few times when talking about the engines used in ‘the expanse’ or in my KSP series. But what you’re talking about sounds like the Ram Augmenter Interstellar Ramjet, but it’s backwards, the interstellar medium is mostly hydrogen which is hard to fuse compared to Deuterium/Tritium so RAIR carries along fusion fuel and uses collected interstellar medium as inert reaction mass.
Such satellites would be perfect platform for kinetic warheads against ICBMs. Guys in Pentagon should be very very interested in further development of the technology.
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.
Okay, blast through a short arc of the upper atmosphere with a ram-jet, collecting a couple of tons of gas. The ship would have solar cells to run the processing of the fuel, but they would fold back behind the cone of the scoop while the craft makes a dive through the atmosphere. Twenty minutes of atmospheric drag, twenty days of processing the fuel and regaining momentum. As long as the energy gained from the exhaust gas was higher than energy lost to momentum, you'd be fine. Giving the ship more time to add solar energy makes sure the gas can be expelled at very high velocities. As far as staying in the top edge of the atmosphere, you'd only do that for research flights (spy satellites and gravity experiments), and flights like these know the end is nigh.
Hi Scott, they could install some high frequency Ultraviolet LED lasers to pre-ionize the air (about 80nm wavelength), maybe aimed in a cone area in the front part of the intake of the engine. Then use magnets to compress the ionized air and finally apply a stronger effect (like microwaves/RF or IR lasers to heat/energize the air) to the compressed air to increase the output energy. It would require more power probably (we'd need fusion or fission reactor or some fancy Elon Musk batteries) but you could even use it as a high thrust/high ISP engine even at low altitudes. You could replace chemical engines altogether.
Not yet they don't, but they are some teams looking at getting down to under 100nm LED lasers. The other option is an F2 or Ar2 Excimer laser. They can get to 140nm to 150nm, not exact but it's close. You'll lose some efficiency but it would still ionize to a degree.
It's not possible for solid state electroluminescent emitters to go below like 100nm. The material with the widest bandgap is 14eV for lithium fluoride and it's absorbent starting at like 12 eV.
yeah - No. you are not even close. didn't you listen? Particle distance in the tens of cm or even meters. you'd have to use a couple thousand Watt to get a chance at significantly ionizing anything there. Just a huge waste of power.
At lower altitudes it should work well, and you can carry some regular compressed air in tanks for higher altitudes. Less expensive than carrying Xenon and easier to obtain. Also, if you're moving fast enough, even a large particle distance will still net you enough gas to work with.
They only say that it will "extend then life of the satellite. They obviously know that it wont permanently, but if it can last, lets say, twice the length of a normal satellite and cost less that twice as much to build and launch it can really help their long term scientific projects.
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?)
And I thought that Poland couldn't help ESA, but 6:59 proved me wrong. GO ESA! Scott What do you think about US Air Force etc. releasing their UFO tapes?
Interesting. Depending on the fuel storage capabilities these Spacecrafts might be able to change orbits frequently, which would enable them to fly to different dead sattelites and might slow them down to crash them at a desired place - cleaning up the sky. 🙂
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.
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!
A high temperature silicon carbide matrix nuclear reactor would be ideal for a long life air fueled ion thruster mainly because it could use the heat and radioactivity to do the work of converting the gases to plasma then all that's left is the acelleration which is basicly electrostatic fields. It would run well for decades 🤓
I was waiting for a mention of the Humanity Star, deorbited after 2 months ans was expected to go for 9. Probably due to being so light for its size, basically a beach ball disco ball hybrid.
When you started talking about intake design and efficiency, it got me wondering about magnetic scoops, such as Bussard's ramscoop. Mind you, such a scoop may end up needing massive amounts of power for even a kilometer wide cone, so may not be as effective? Also, I started to wonder: If we do end up running breathing ion engines, what will happen to the air molecules after they fire out of the back of the engine. New fields of research!!
Nothing really. They turn into ionized particles (electrically charged particles). They will lose their charge after a while. Maybe they react with other particles. But after all they turn into normal "air" again.
Jimfoxyboy That would depend entirely on whether they're stopped by collisions with other particles on the way out. If the mean distance between collisions is on the order of a meter, then they most certainly will since it's quite a few meters before they're properly out of the atmosphere. In any case, since they're charged particles, they'd end up captured by the earth's magnetic field if they were to somehow escape.
And more. Ion is a very interesting technology because it's high ISP but noble gases are expensive and mainly collected on Earth. Open ion to oxygen means that fuel could be collected from a lot different extraterrestrial sources as most NEOs has oxygen in one form or another. A infrastructure of tethers could use ion as a constant thust to be accumulated on rail or rotatory launchers to produce high thrust in spaceships while ion provide constant and efficient fuel to speed conversion.
As mentioned oxygen is a very reacting material. I think that it would corrode the engine very fast. It is known from chemical engines (which use oxygen to keep the flame burning), that corrosion is a thing.
I agree with that. But how overcome this problem? The solution would be the materials of the engine have to be not reactive to oxygen. But you need a reaction as well...
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?
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.
Scott now you should calculate if it could fly a super low orbit on Mars, perhaps with an RTG instead of solar panels, and perhaps with an RTG around any of the gas giants, Titan, and maybe even Pluto. I imagine for Mars it would work with a very low orbit, with Pluto I have doubts. Any chance of doing this in KSP? We would need much more altitude to be calculated for planetary atmospheres with tiny drag though, in addition to the new ion engine / intakes. Kerbin, Duna, Jool and Laythe all await your eternal atmospheric orbiter things!
depth386 RTGS aren't really that good. They mainly just provide supplementary power and power when there is no sun. Also Pluto has virtually no atmosphere so you can use a normal sat
Ausintune sorry you’re right, RTG would need a lot of heat exchanger type stuff to provide the kilowatts necessary. There is an RTG powered car but in earth’s atmosphere it’s easy to use a closed steam cycle and radiator or something to derive big power. Regarding pluto lol yeah I was thinking about a freakishly low orbit though. Practically grazing the mountains. Imagine a mars orbital mapper orbiting at like peak of olympus mons altitude in a north-south orbit. The map resolution might be really hot ;-)
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.
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 ?
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.
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.
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.
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'.
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.
_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💃💃
"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-
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.
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 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
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.
Sir your videos are truly fascinating. You are teaching me things i had no idea about... thank you.
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.
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.
"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."
Boy!!!! I can remember when the coverage map shown at 1:33 was really a very high secret!
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...)
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.
The glow on those engines reminds me of something from Homeworld or something. So cool.
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?
6:23 what what? What are all these thrusters? TEACH ME SCOTT MANLEY, I WANT TO FLY SAFE
These kind of videos are my favourite from you
this is very cool, for some reason its very cool to me imagining things circling earth in artificial orbits just skimming the atmosphere
I love how in the cold war basically they just put nuclear for any energy problem
This was very interesting, thank you. And yes, oxygen is very corrosive.
Jack Vernian only if metal isn't oxidised
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
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.
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
Looking forward to someone porting this sort of engine to KSP.
How does a guy that started a channel about video games know so much cutting edge engineering and spec details !?!
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.
There is no prase as calming as "old sovjet reactors"...
I just saw this episode Scott that it is just really interesting!!
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.
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.
The second satellite image at 1:46 is actually the Hungarian city Szeged!
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.
I really enjoy videos like these.
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...
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
this definitely needs a follow up video, with more details, more explanations
Waiting for papers I can read
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
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.
Funny how the newest regime of extraterrestrial exploration is the space *closest* to Earth.
Great achievement!
Still waiting for *intra* terrestrial exploration to progress beyond (literally) scratching the surface...
for the US's part thats because other than Musk we dont really have any launch capability (and his less capable competitors).. because obama effectively ended our space program. Which imho resulted from the boondoggle we called the shuttle. You can be sure the russians, europeans, japanese, indians et al are continuing development howevr. It's just that our press tends to only cover it's own nations space programs for the most part
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.
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.
The thumbnail has a cool optical illusion
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...
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.
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.
3:00 The soviet unions nuclear satellites are an interesting story. When the reactor core was ejected from the satellite and boosted to a higher orbit, the mechanism obviously broke the coolant lines. The sodium potassium used formed small droplets which now orbit in a bunch of places between the graveyard orbit and LEO. Quite an annoying form of space debris
Scott Manley -- There are a few questions/comments this concept has "re-ignited" ;) about Bussard Ramjets. To go faster and faster and finally get close to lightspeed, using only in-situ propellant? Never happen, that is a juvenile fantasy. Bussard Ramjet is still a jet, so it has Inlet Drag, which must be overcome by exhaust force and velocity higher than inlet drag and velocity. But fusion can only make exhaust velocity of about 5% of c. Still, *a modified version can work very easily* at a wide range of speeds, without needing any kind of nuclear power, or chemical combustion. The trick is to gather in the oncoming matter, add reaction mass to it, then expand it gradually away, along and behind the craft. Same energy into more mass makes a net thrust. But you have to bring reaction mass along, and get some initial velocity by other means. For a starship, even sand will do for the reaction mass. In the atmosphere, working towards orbit, you need hydrogen... not to burn inside engines, but to have lower average molecular weight in the exhaust than in the oncoming air it gets mixed with. It will burn, but mostly far behind the craft, where it cannot produce thrust. This little-known trick of _adding inert mass to make net thrust_ is worthy of a video, imho.
I’ve mentioned inert mass injection a few times when talking about the engines used in ‘the expanse’ or in my KSP series. But what you’re talking about sounds like the Ram Augmenter Interstellar Ramjet, but it’s backwards, the interstellar medium is mostly hydrogen which is hard to fuse compared to Deuterium/Tritium so RAIR carries along fusion fuel and uses collected interstellar medium as inert reaction mass.
Interesting concept honestly.
Turbomolecular pump stages should increase collection efficiancy
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
@@Zero2222-z4u corona actually means crown in Latin so both the virus and the solar features derive their name from there.
Such satellites would be perfect platform for kinetic warheads against ICBMs. Guys in Pentagon should be very very interested in further development of the technology.
6:50 I believe its more like a ram scoop. The initial orbital launch will provide that speed.
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.
Okay, blast through a short arc of the upper atmosphere with a ram-jet, collecting a couple of tons of gas. The ship would have solar cells to run the processing of the fuel, but they would fold back behind the cone of the scoop while the craft makes a dive through the atmosphere. Twenty minutes of atmospheric drag, twenty days of processing the fuel and regaining momentum. As long as the energy gained from the exhaust gas was higher than energy lost to momentum, you'd be fine. Giving the ship more time to add solar energy makes sure the gas can be expelled at very high velocities.
As far as staying in the top edge of the atmosphere, you'd only do that for research flights (spy satellites and gravity experiments), and flights like these know the end is nigh.
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.
This is awesome!! could also be used for communication and internet satellites.
Lower latency and better signal strength and so forth...
Hi Scott, they could install some high frequency Ultraviolet LED lasers to pre-ionize the air (about 80nm wavelength), maybe aimed in a cone area in the front part of the intake of the engine. Then use magnets to compress the ionized air and finally apply a stronger effect (like microwaves/RF or IR lasers to heat/energize the air) to the compressed air to increase the output energy. It would require more power probably (we'd need fusion or fission reactor or some fancy Elon Musk batteries) but you could even use it as a high thrust/high ISP engine even at low altitudes. You could replace chemical engines altogether.
LEDs don't go below 200nm.
Not yet they don't, but they are some teams looking at getting down to under 100nm LED lasers. The other option is an F2 or Ar2 Excimer laser. They can get to 140nm to 150nm, not exact but it's close. You'll lose some efficiency but it would still ionize to a degree.
It's not possible for solid state electroluminescent emitters to go below like 100nm. The material with the widest bandgap is 14eV for lithium fluoride and it's absorbent starting at like 12 eV.
yeah - No.
you are not even close.
didn't you listen? Particle distance in the tens of cm or even meters. you'd have to use a couple thousand Watt to get a chance at significantly ionizing anything there. Just a huge waste of power.
At lower altitudes it should work well, and you can carry some regular compressed air in tanks for higher altitudes. Less expensive than carrying Xenon and easier to obtain. Also, if you're moving fast enough, even a large particle distance will still net you enough gas to work with.
Need this video needs to be updated
"...Satellites in the Corona program..."
me: imediately checking the date of this video
They only say that it will "extend then life of the satellite. They obviously know that it wont permanently, but if it can last, lets say, twice the length of a normal satellite and cost less that twice as much to build and launch it can really help their long term scientific projects.
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?)
So ESA just built the first in orbit fuel scoop. Nice!
It's a good idea to avoid decay. EM drive may do that if it really worked.
And I thought that Poland couldn't help ESA, but 6:59 proved me wrong. GO ESA! Scott What do you think about US Air Force etc. releasing their UFO tapes?
Interesting. Depending on the fuel storage capabilities these Spacecrafts might be able to change orbits frequently, which would enable them to fly to different dead sattelites and might slow them down to crash them at a desired place - cleaning up the sky. 🙂
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.
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!
Catching spy satellite canisters in mid-air, that sounds like an exciting job.
Great video and information
A high temperature silicon carbide matrix nuclear reactor would be ideal for a long life air fueled ion thruster mainly because it could use the heat and radioactivity to do the work of converting the gases to plasma then all that's left is the acelleration which is basicly electrostatic fields. It would run well for decades 🤓
This was a really fascinating video! Thank you for sharing. I had no idea old Russian nuclear sats were orbiting the earyh
I was waiting for a mention of the Humanity Star, deorbited after 2 months ans was expected to go for 9. Probably due to being so light for its size, basically a beach ball disco ball hybrid.
Two years on Scott - any update on this technology?
When you started talking about intake design and efficiency, it got me wondering about magnetic scoops, such as Bussard's ramscoop. Mind you, such a scoop may end up needing massive amounts of power for even a kilometer wide cone, so may not be as effective? Also, I started to wonder: If we do end up running breathing ion engines, what will happen to the air molecules after they fire out of the back of the engine. New fields of research!!
Nothing really. They turn into ionized particles (electrically charged particles). They will lose their charge after a while. Maybe they react with other particles. But after all they turn into normal "air" again.
Considering how fast they get shot out as exhaust, I also wondered if the particles just end up leaving orbit all together...
Jimfoxyboy That would depend entirely on whether they're stopped by collisions with other particles on the way out. If the mean distance between collisions is on the order of a meter, then they most certainly will since it's quite a few meters before they're properly out of the atmosphere. In any case, since they're charged particles, they'd end up captured by the earth's magnetic field if they were to somehow escape.
love you scott huge fan keep it up :)
This could be useful for satellites providing internet connectitvity from low altitudes.
Something like this would make possible low latency satellite internet service available for the entire planet.
Bussard ramjets when?
Aaah. Quality content.
Hey Scott, could you do an episode on how steam-powered rockets work (like the piddly one Mad Mike Hughes just launched)?
And more. Ion is a very interesting technology because it's high ISP but noble gases are expensive and mainly collected on Earth. Open ion to oxygen means that fuel could be collected from a lot different extraterrestrial sources as most NEOs has oxygen in one form or another.
A infrastructure of tethers could use ion as a constant thust to be accumulated on rail or rotatory launchers to produce high thrust in spaceships while ion provide constant and efficient fuel to speed conversion.
As mentioned oxygen is a very reacting material. I think that it would corrode the engine very fast. It is known from chemical engines (which use oxygen to keep the flame burning), that corrosion is a thing.
That is the reason because it would be a breakthough if there is a way to avoid the corrosion and make good ISPs with oxygen.
I agree with that. But how overcome this problem? The solution would be the materials of the engine have to be not reactive to oxygen. But you need a reaction as well...
It's a ion engine. You don't need a chemical reaction but a electric/electrostatic one.
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?
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.
Air breathing ion thruster.... Sounds good
Scott I was literally thinking about this exact idea, how did you read my mind
Scott now you should calculate if it could fly a super low orbit on Mars, perhaps with an RTG instead of solar panels, and perhaps with an RTG around any of the gas giants, Titan, and maybe even Pluto. I imagine for Mars it would work with a very low orbit, with Pluto I have doubts.
Any chance of doing this in KSP? We would need much more altitude to be calculated for planetary atmospheres with tiny drag though, in addition to the new ion engine / intakes. Kerbin, Duna, Jool and Laythe all await your eternal atmospheric orbiter things!
depth386 RTGS aren't really that good. They mainly just provide supplementary power and power when there is no sun.
Also Pluto has virtually no atmosphere so you can use a normal sat
Ausintune sorry you’re right, RTG would need a lot of heat exchanger type stuff to provide the kilowatts necessary. There is an RTG powered car but in earth’s atmosphere it’s easy to use a closed steam cycle and radiator or something to derive big power. Regarding pluto lol yeah I was thinking about a freakishly low orbit though. Practically grazing the mountains. Imagine a mars orbital mapper orbiting at like peak of olympus mons altitude in a north-south orbit. The map resolution might be really hot ;-)
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.
"Lowest ceiling" that'd be floor or deck :P
Very interesting video
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 ?
Please Scott, never get rid of that intro :) it's perfect
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.