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#1 2024-03-10 12:44:05

Void
Member
Registered: 2011-12-29
Posts: 7,394

Air Breathing Orbital Propulsion Methods (VELO)

Air Breathing Orbital Propulsion:
https://www.msn.com/en-us/news/technolo … r-BB1j259A
Quote:

‘Air-breathing’ propulsion tech could unlock unlimited propellant for satellites
Story by Chris Young • 1w • 3 min read

Very Low Earth Orbit (VLEO), situated at an altitude between 100 and approximately 450 km (most commonly 250-350 km) is becoming increasingly attractive for both commercial and scientific endeavours. "It is easier to get to, requires fewer resources for communications, and allows for smaller payloads.

I had previously seen reference to a European device: https://www.esa.int/Enabling_Support/Pr … 20payloads.  Quote:

ESA seeks space applications ideas in Very Low Earth Orbit
18/10/2023
3287 VIEWS
35 LIKES

Image Quote: GOCE_in_orbit_pillars.jpg

Frankly after that is achieved, I would like to see orbital power stations that can tow these devices to collect air from the upper atmosphere.
It may be that tethers electrified could be the propulsion method for that.  Instead to dumping the materials, for propulsion they would be collected so as to load propellants to interplanetary or Lunar spacecraft.

The electrified tethers might push off of the Earth's magnetic field.

Such a device might work for Jupiter, Saturn, Uranus, Neptune.  For Venus, Mars, and Pluto, somehow the solar wind might be the method of propulsion.

Done

Last edited by Void (2024-03-10 12:54:34)


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#2 2024-03-10 13:19:03

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 18,142

Re: Air Breathing Orbital Propulsion Methods (VELO)

This post is reserved for an index to posts that may be contributed by NewMars members over time.

The link provided in Post #1 leads to an article that reveals at the ** very ** end that this system needs a bit of work before it can go into production.

On the ** other ** hand, the proposal was well enough regarded that it received preliminary funding from a government agency.

The sticking point is how to insure that there is an equal output of charged particles, so that the net effect of operation of the system is neutral.

The article spends most of it's content talking about how wonderful this system would be if it ever works.

I'm hoping NewMars members will keep a close eye on this venture.

Howevr, any investor would be wise to steer clear until the "technical issues" are solved.

(th)

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#3 2024-03-11 08:35:16

Void
Member
Registered: 2011-12-29
Posts: 7,394

Re: Air Breathing Orbital Propulsion Methods (VELO)

Well, this is nerd food: https://www.youtube.com/watch?v=kO3ENmbQQ9o
Quote:

Introducing: Ascender H1 Variant Orbital Airship

John Powell
3.21K subscribers

If the members need to, then hammer away.  I am only providing awareness of the video.

Done

Last edited by Void (2024-03-11 08:36:43)


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#4 2024-03-11 09:06:12

tahanson43206
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Registered: 2018-04-27
Posts: 18,142

Re: Air Breathing Orbital Propulsion Methods (VELO)

For Void re #3

Thank you for providing this update on the work of John Powell....

NewMars members may recall the name.

It has come up previously. I am glad to see the update.

Here is a list of posts that contain "John" and "Powell" and which also related to the balloon effort.

Re: Planetary transportation » Balloon or dirigible for Mars "hot air" or gas filled » 2023-09-09 08:34:00
tahanson43206

Re: Interplanetary transportation » Airship to Orbit? » 2021-12-17 14:32:47

Re: Interplanetary transportation » Un- conventional ways to LEO » 2020-11-28 09:46:29

Re: Science, Technology, and Astronomy » Technology Updates » 2020-06-17 11:39:59

Re: Interplanetary transportation » Compressed gas balloon rocket for Mars launch » 2020-06-06 14:40:08

Re: Interplanetary transportation » Balloon Landing System from Phobos to Mars » 2020-05-14 12:18:38

Re: Interplanetary transportation » Airship to Orbit? » 2020-01-01 23:57:50

Re: Planetary transportation » Dirigibles on Mars - A practical means of transport? » 2019-12-31 21:07:05

Re: Science, Technology, and Astronomy » Newmars Book Club » 2019-05-20 13:20:05

Re: Human missions » Calling our technical experts - Any chance this thing works? » 2005-08-29 09:29:21

I note that the earliest post dates all the way back to 2005 .... It is nearly 20 years later, so I am glad to see the link posted in #3 is available for an update.


(th)

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#5 2024-03-11 10:17:48

Void
Member
Registered: 2011-12-29
Posts: 7,394

Re: Air Breathing Orbital Propulsion Methods (VELO)

That is encouraging.

https://en.wikipedia.org/wiki/JP_Aerospace

I would like to know more about there engines, and if they could breath air somehow.

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#6 2024-03-11 10:31:19

Calliban
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From: Northern England, UK
Registered: 2019-08-18
Posts: 3,572

Re: Air Breathing Orbital Propulsion Methods (VELO)

Void, this is an interesting new topic.  I think it could work, but it will be a difficult engineering job to build a spacecraft that can harvest Earth's atmosphere from orbit.  Because the atmospheric ions will be hitting your scoop at a velocity of about 7.7km/s, your spacecraft will need a propulsion system with an exhaust velocity somewhat greater than this to maintain its orbital speed.  Presumably, it would use some of the gathered air as propellant.  There would also be a non-trivial amount of heat generated as you cool down the atmospheric ions that are entering the scoop at 7.7km/s.  But I think it could work.  Ion propulsion using nitrogen as propellant would appear promissing.


"Plan and prepare for every possibility, and you will never act. It is nobler to have courage as we stumble into half the things we fear than to analyse every possible obstacle and begin nothing. Great things are achieved by embracing great dangers."

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#7 2024-03-11 12:39:12

Void
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Registered: 2011-12-29
Posts: 7,394

Re: Air Breathing Orbital Propulsion Methods (VELO)

Yes, high speed accumulation is going to be difficult.

I wonder though if the ship could tank up on atmosphere before going to high speed.

Then as it might be able to move to a high speed, could a rotavator give it assistance to orbit.

Granted the junk problem in orbit will be an impediment to that.

Anyway, I think this tech might be as much as 50 years off if it can be done at all.

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#8 2024-03-11 17:35:18

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 29,310

Re: Air Breathing Orbital Propulsion Methods (VELO)

Semm quite possible to be collecting the castoff from the solar wind but we are talked about the syphoning of that atmosphere as well.

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#9 2024-05-16 22:17:50

Void
Member
Registered: 2011-12-29
Posts: 7,394

Re: Air Breathing Orbital Propulsion Methods (VELO)

This is a hard path, but it seems that it is being looked into: https://www.youtube.com/watch?v=LpGCN-qH9VE
Quote:

Air Breathing Electric Propulsion - High Concept Satellite Dream or Soon to be Reality?

Tom Dune - UK Space News

More from the query: https://www.bing.com/search?q=Air+Breat … 8D&pc=U531

https://www.esa.int/Enabling_Support/Sp … c_thruster

Here is a bit about the 1959 PROFAC (Mentioned in the video): https://forum.nasaspaceflight.com/index … ic=17984.0
Quote:

Author Topic: Scooping atmospheric air (PROFAC revisited)  (Read 66861 times)
Offline alexterrell
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Scooping atmospheric air (PROFAC revisited)
« on: 07/22/2009 02:07 pm »
Following a discussion here (http://forum.nasaspaceflight.com/index. … c=17776.75) , I was wondering if anyone was revisiting the PROFAC concept of the 1960s.

http://www.bisbos.com/rocketscience/spa … rofac.html

Profac required a 10MW nuclear reactor, which is probably not feasible in a 120km orbit. So how about we revisit it using tethers.

I propose:
An accumulator module at an altitude of 120km, consisting of:
- a 4m diameter scoop, imposing a drag of 500N, and collecting 3 tons of air per day (assuming 50% capture)
- A compressor, and heat rejection radiators. I estimate this needs about 50 KW.
- Two tanks for liquid air.

A mother ship, orbiting at about 320km, consisting of:
- Solar power
- Electrodynamic reboost facility
- Tether deployment mechanism, for raising and lowering both the accumulator module, and the air tanks.
- Liquid air storage and separation facilities
- A housing for the accumulator stage when it's reeled in so it can be maintained in a shirt sleeve environment
- Optionally, a crew visiting module.
- Tether repair facility
- A counter balance to keep the main elements of the mother ship at zero g.
- A HVDC connection to the Accumulator to power the compressor. (Can you send DC over 200km through the Earth's magnetic field - or do we need a laser?).

The whole mission would be launched by an Ares V or a Jupiter 232. The mother ship would then deploy the accumulator and lower it 200km, where it would scoop up about 3 tons per day of air (about 20 tons of oxygen per month).

The accumulator would be linked by a number of hoy-tethers, so it can be reeled in.

When one of the air tanks is full, it would be reeled up to the mother ship over a day or so (<10km/hr).

A repair unit can move between the accumulator unit and the mother ship to replace broken stands of fibre. (Probably spectra 2000).

Once every few years, the accumulator can be reeled into the bay of the mother ship, the doors closed and the bay pressurised. A visiting Orion crew will carry out maintenance and replace the tether reels.

Question: 1. I can't get a figure for electrodynamic thrust in N/KW. I assume the accumulator has a 500N counter force. The tethers and mother station will bring this to below 1KN. Given day time operation only, probably want to scale for 2KN of thrust. What power is needed for this?

2. Would this concept be worthwhile, in the medium term for supporting constellation, and in the long term for supplying nitrogen to space. Apart from breathing air in lava tubes etc, does nitrogen have a use?

3. Any other improvements or major issues?



« Last Edit: 07/23/2009 09:24 am by alexterrell »

So, I have a notion of a rotavator with two engines the alternately dip into the atmosphere to propel against the thin atmosphere,  and to collect atmosphere.  Solar panels at the hub.

But it is a very big major ask.

Worlds where this could be used would be any with a equal to that of Mars or better.  But in many non-Earth cases, nuclear may well be better than solar power.  Solar power might be OK for Venus though.

So, I think it would be very useful to be able to tank up with atmospheric gasses of any kind, from orbit.

But the idea has a long way to go, I am sure, and it may not be possible.  But if it can work for any world, that would be important.

Possible worlds to use it around: Venus, Earth, Mars, Jupiter???, Saturn & Titan, Uranus, Neptune & maybe Triton, Pluto.

Perhaps in 50 years or so.  I have been told that ideas take that long to become real.
But this was considered in some way back in 1959.

Done

I presume that worlds with atmosphere and a relatively low gravity, may work the best.  Mars and Titan perhaps, maybe Triton.

Done

Last edited by Void (2024-05-16 22:43:18)


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#10 2024-05-17 09:59:23

Void
Member
Registered: 2011-12-29
Posts: 7,394

Re: Air Breathing Orbital Propulsion Methods (VELO)

Here is another recent article: https://www.msn.com/en-us/news/technolo … 9621&ei=12
Quote:

This innovative concept, called air-breathing electric propulsion spacecraft, will fly near our planet in the very low Earth orbit (VLEO). This orbit is between 95 and 250 miles in altitude. This orbital location has the potential to dramatically improve Earth observation, climate monitoring, and satellite communications.

The center recently received £250,000 from the UK Space Agency to advance the development of the air-breathing electric propulsion concept. This grant will enable them to create a conceptual design, perform propulsion tests, analyze orbital mechanics, and perform aerodynamic simulations.

I am very interested in this.  But it needs time for its full potential, whatever that is to be discovered.

Done

Last edited by Void (2024-05-17 10:02:33)


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#11 2024-06-19 14:47:59

Void
Member
Registered: 2011-12-29
Posts: 7,394

Re: Air Breathing Orbital Propulsion Methods (VELO)

Here is another article about it: https://www.youtube.com/watch?v=Lz4O6AzLofQ
Quote:

Satellites That Scoop Air And Use It As Propellant

Fraser Cain
440K subscribers

I have some hope that it may work, and if it does, can it be added to a tether system.

A solar panel out of the high drag, might have a spinning tether that dips these engines into the atmosphere.  But and adsorption device might also be added to the total device, and perhaps the transmission of power to the engines by cable, lasers, or microwaves.  It may never work, but I am excited to see chances at all.

If it ever works for Earth, it might work for other planets with atmospheres.

Done

Last edited by Void (2024-06-19 14:52:22)


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#12 2024-06-19 16:10:14

GW Johnson
Member
From: McGregor, Texas USA
Registered: 2011-12-04
Posts: 5,615
Website

Re: Air Breathing Orbital Propulsion Methods (VELO)

Most of the people who propose such things have absolutely no idea how supersonic inlets really work.  I do,  which is why I am more-than-skeptical of such notions.

GW


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#13 2024-06-19 19:33:42

Void
Member
Registered: 2011-12-29
Posts: 7,394

Re: Air Breathing Orbital Propulsion Methods (VELO)

OK, then I can sign on with you and say that they will have to prove it.

They did make me think that if a way could be found to drop a new bottle of Xenon down from a higher orbit, perhaps that could help.
That is if that low orbit is that valuable.

Done

Last edited by Void (2024-06-19 19:35:10)


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#14 2024-06-19 20:16:44

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 18,142

Re: Air Breathing Orbital Propulsion Methods (VELO)

For Void re #13

I think that the way you worded your message to Dr. Johnson implies you might be willing to learn how supersonic inlets work.

I hope that is the case, because the forum (or at least a ** few ** members ) would greatly appreciate a tutorial on this very challenging subject.

I am enlisting your skills in presentation in hopes you will decide to take this on.  We have a complete course on how to set up a flight in the Solar System, and to this point, not ** one ** member of the forum has confessed to having actually studied the material, or even downloaded any of the many spreadsheets.

If you would like to take the lead on this, the time frame should be set in weeks or months, because everyone who follows along will need time to read the materials that may be presented, or to watch the videos if they become available.

A sound understanding of supersonic or hypersonic flight is right in the ballpark for this forum.

The method I am hoping you will be willing to consider is a dialog with a domain expert who also has communications skills, and a willingness to help a complete novice.  Such a willingness is most unusual, as you may well already know.

(th)

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#15 2024-06-20 11:24:57

Void
Member
Registered: 2011-12-29
Posts: 7,394

Re: Air Breathing Orbital Propulsion Methods (VELO)

I am in a bit of an awkward position. 

We need to not get into the position of playing "Pope and Heretic".  There is a saying, "Never wrestle with a pig it wastes your time and it annoys the pig".  In this case, I would be the pig.  I could put some lipstick on, but I think I would not be able to produce a value.  A great deal of time could be wasted.

I have read that a lesser mind will only see a mirror when evaluating a greater mind, but the greater mind can understand the lesser mind to a greater extent.

And I have the issue of age.  I used to do some programming where I worked.  I will not say it was worthy, but I did what I had to and was always on the knife edge of keeping things functional.  I got away with it but realized that I was not a movie star of programming.  I also realized that the entire 3rd world could do programming at a distance, so, I will likely become outdated very soon.  And now AI can do programming, I presume better than macros in Excel.  So, I saw that investment of effort into it was not my best play, not the best investment of my time.

At my age, I am not likely to become a replicator of music of any significance, and there is no evidence that I will become a composer.  That should have happened a long time ago if it were to happen at all.

I would be very interested in Dr. Johnsons teachings, but I do note that the altitudes at which a VELO system might operate "May" be in the molecular flow of atmosphere and not in the viscous pressures.

I found this calculator which I sort of understand: https://www.omnicalculator.com/physics/ … t-altitude
I think that the altitude minimum would be 100 km, perhaps going as high as 450 km, from what I have read.
I put in the values 1 bar, 100 km, 270 k, and get 0.00000319784 bar, and so, .000319784 mbar, I think, .319784 microbar?

Granted I will not consider those numbers as correctly done, but I have a sort of look at it.

For anything in such a powered orbit attempt, Corrosion, drag, power needs, and effectiveness of propulsion are some of the things that would matter.

For Earth we might be up against an unsolvable situation.  Younger people are working on it.  But for Venus, Mars, and Titan, or the gas giants, then Triton, and Pluto, perhaps something might emerge someday.  So, I feel that a binary evaluation of Yes/No is not yet appropriate.  There could be some utility that may emerge from this, at least a better understanding of the nature of the problems.

And now, I may make the situation more complex.
-Tethers
-Replaceable Propellant Tanks.

For Tethers, of a spinning type it may be possible to address the atmosphere in a periodic dip of the engines into the atmosphere at an altered speed and altitude.  This may even allow dipping low enough to get into a viscous pressure of atmosphere.  But a scoop may not directly send propellants from the atmosphere to an engine, but you might dip an adsorption device into the atmosphere, and then send the collected results to the engines, when it may be most appropriate.  Again, I will mention that there are many worlds where this might be considered for.  On such a machine, a power supply either solar or nuclear may be at the center of the spinning device, away from the large atmospheric drag.  While power could be delivered to the collectors and engines by wire, it might also be delivered by laser or microwave.  This then may allow a low overall atmospheric drag while dipping the tether ends with collection methods into the atmosphere in a spinning fashion.  Of course, spin may be set aside, and you might simply drag a collector though the atmosphere.  It is possible that a device could get down to viscous level of atmosphere for collection of atmospheres.

As for disposable tanks.  I have thought that one solution to a device that may at times fail to collect sufficient propellants is as said in the article in a previous post, to have a tank of Xenon for bridging those episodes.  But could you "Drop" such tanks from a higher orbit and let atmospheric drag move them down so that the engine could catch them and use the propellants?  Perhaps empty cartridges could be released to burn up in the atmosphere. 

The purpose of such an activity would be to nurse the developing technology so that it can pay its way by producing data that could be collected at a low orbit.  The desire would be to eventually have a total atmosphere breathing system, but you might be able to get the thing to be partially breathing by dropping refill cylinders down to the machine.

Done

Last edited by Void (2024-06-20 11:59:26)


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#16 2024-06-21 09:31:00

Void
Member
Registered: 2011-12-29
Posts: 7,394

Re: Air Breathing Orbital Propulsion Methods (VELO)

This happened today: https://newmars.com/forums/viewtopic.ph … 25#p224625
I am not allowed to post on that topic by instruction from (th).
Here is a quote of his post in that location:

tahanson43206
Moderator

Registered: 2018-04-27
Posts: 17,889
Email
For Void re topic about air breathing orbital propulsion methods seems worth developing further.

I don't think Popes or Heretics have much to do with the subject.

You asked Dr. Johnson to prove something to you, when he offered a judgement based upon experience and study.

I offered you an opportunity to take the lead in learning how inlets work at high velocities.  it seems to me the subject would be of interest in all possible regimes.

It will take some work and time to assemble a useful collection of knowledge about the subject you have chosen.

You can buy Dr. Johnson's book about ramjets for $100, as a number of folks have done.

That would be a good place to start.

Or perhaps there are already free presentations on the subject that you might be able to access.

Your topic on Air Breathing propulsion by orbiting vehicles started when you found an article on the subject.

(th)


Sub Quote:

You asked Dr. Johnson to prove something to you, when he offered a judgement based upon experience and study.

  I have reviewed posts #12 and #13,  I do not see that that is true.

Sub Quote:

I don't think Popes or Heretics have much to do with the subject.

What you say you think is what you say you think, or what you think to say.  A typical binary conflict involves a hierarch, possibly of dogma, and a conflict with new concepts which may or may not be useful.  I did not feel like I want to engage in such behaviors and that the probable outcome would not be useful.

Dr. Johnsons books may contain important and useful information.  I expect that his mind contains even better information.  But we have not consented to have a dialog on the situation.  I see myself as audience, and not a player.  I don't have the correct common language to even formulate appropriate questions.

I know that Dr. Johnson has indicated work with ablative heat shields, so he must understand the effects of rarified atmosphere, even that high.

I have looked some things up:
The Scramjet is the highest operating Scramjet is said to be: https://aviation.stackexchange.com/ques … 75%20km%29.
Quote:

250,000 ft
A Scramjet engine, which is still technically an Air breathing engine, will provide the highest possible service ceiling. Theoretically, they can operate at up to 250,000 ft (75 km).

This article seems to suggest that VELO might work in a certain range: https://www.msn.com/en-us/news/technolo … 9621&ei=12  Quote:

This orbit is between 95 and 250 miles in altitude.

This converter is of use: https://www.unitconverters.net/length/miles-to-km.htm
Quotes:

Result: 95 mile = 152.88768 kilometer

Result: 250 mile = 402.336 kilometer

So, according to the above, the highest theoretical air breathing engine "Tops Out" at ~75 km below the lowest VELO device supposed to be possible.  Because of what I think was Dr. Johnson's work history, I suspect he has useful information for this even if it is not in the area of Combustion Air Breathing devices.  (VELO being outside of that).

This seems to have exposed something else that is rather interesting: https://newmars.com/forums/viewtopic.ph … 75#p224275  For the latest Starship atmospheric Entry: Quote:

Flap Control at 85 km, 26,719 speed.
Peak Heating at 71 km, 25,832 speed.
End of temperature rise at 68 km, 24,000 speed.
Particles Apparent at 68 km, 22,263 speed.
Increased Pressures at 62 km, 20, 287 speed.
Burning Through seems to start at 55 km, 14,738 speed.

So, it may be that a Scramjet vehicle could rise up to a Starship skipping off of the atmosphere: SubQuote:

End of temperature rise at 68 km, 24,000 speed.

But of course that would be very, very, nasty to pull off, a convergence of vehicles.  Maybe the speeds could not match either.  I am not sure.  But it is a bit interesting.

Anyway. there are at least two entities working on VELO, one in North America, and one in Europe.

Done

Last edited by Void (2024-06-21 10:21:33)


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#17 2024-06-21 12:41:26

GW Johnson
Member
From: McGregor, Texas USA
Registered: 2011-12-04
Posts: 5,615
Website

Re: Air Breathing Orbital Propulsion Methods (VELO)

Void:

I think you can capture samples of gases from a very low satellite,  but these will essentially be closed containers of extremely low-density gas when you pull them aboard.  Very tiny masses inside the containers. 

I do not think you can capture such gases in quantity rates sufficient to use those gases for any kind of propulsion. 

The density is just too low,  and  at orbital speeds,  the compression capability of any imaginable inlet will be vanishingly low.  The shocks are simply too strong to manage in any effective way.  And there would be no materials that could withstand contact with such plasma and sill maintain a useful shape,  and hot plasma it would be:  crudely an effective 8000 K at 8 km/s velocities.

GW


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#18 2024-06-21 12:55:15

Void
Member
Registered: 2011-12-29
Posts: 7,394

Re: Air Breathing Orbital Propulsion Methods (VELO)

Well, thankyou Dr. Johnson.  I will accept your descriptions of impediments, as I have no ability to dispute them.  As I have said before, the VELO people are going to have to prove that they can do what they propose to do, and I cannot evaluate their notions, nor is it a task appointed to me to do so.

I do leave open the concept that other worlds might be more suitable and that alternate methods may be possible to consider, such as feeding bottles of Xenon to a Very Low Orbit device.  That idea would be to drop them from a higher orbit and use atmospheric friction to assist them to get close enough to the low orbiter for it to catch them.

Also, a rotavator may allow a bending of the rules, but Earth has too much space junk for that I fear, and also, we are not yet capable of building things on that scale.

Done

Last edited by Void (2024-06-21 12:58:51)


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#19 2024-06-21 13:13:57

Void
Member
Registered: 2011-12-29
Posts: 7,394

Re: Air Breathing Orbital Propulsion Methods (VELO)

I also see an interesting potential that may emerge over time.  If bottled propellants could be delivered to an engine that can move up and down though low orbits which are prone to decay, it might be possible to reduce the altitude that a ship like Starship has to go to for delivery of cargo.  And if energy projection becomes possible, then this might also facilitate it.

The capabilities are not fixed.  For instance, electric rocket engines are not entirely discovered as per possible capabilities.  And power delivery methods are not a completed field either.  For instance, power could be projected from the ground or from orbit.

As I understand it Starlink has its own Krypton thrusters, so that I think they are dumped out at a lower orbit and climb higher.

So, a bottled method that moved from 150 km to 450 km, where also power augmentation from beamed projection might be possible this then would perhaps solve some of the problems of an air breathing device, other than the air breathing.  As I have said, they will have to prove that they can do the air breathing with their device.

Done

I see that the ISS is ~400 kilometers.

Done

Last edited by Void (2024-06-21 13:20:11)


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