The thread for space cadets!

[hobbsyoyo]

So if you place a ship in space above the Earth and you have unlimited fuel, you could 'hover' by cancelling out the pull of gravity and then with another engine push the ship forward at whatever speed you want. This is not an orbit, it's just fancy free flying even though it's in space.

The ISS is not continuously firing engines, it does periodic reboosts using docked ships to counteract atmospheric drag. Each upward jump on this altitude graph represents a reboost, they happen about once a month or so.

There is a cool proposal from the Europeans to use an air-breathing electric engine which would take in rarefied atmospheric gases at very low orbital height (~200 km) so that it can continuously skim the upper atmosphere without re-entering. But the key thing here is that it can't stop or even slow down - it has to keep burning that engine to stay at the velocity required to stay at that height. If it goes faster, it will rise; slower and it will sink back in. It has no ability to really adjust the velocity of its orbit without changing the orbit itself.

 

[hobbsyoyo]

At the end of last month, NASA announced they had selected three companies to provide human lunar landers for their Artemis mission.

Blue Origin's 'national team' effort was selected with the most funds. This is a three-element lander with parts from Blue, Lockheed Martin and Northrop Grumman.

Spoiler :

Huntsville-based Dynetics has a single-piece lander that uses novel propellant drop tanks.

Spoiler :

The biggest shock was that NASA also selected SpaceX's Starship system (modified for lunar landing) as the third entry:

Spoiler :

None of these missions require or even desire to use the SLS for launch. They SLS will still be notionally used to transport Orion (the crew capsule) to lunar orbit to rendezvous with these landers, but with the inclusion of the Starship system, it's clear Jim Bridenstine (NASA chief) is hedging his bets against that ill fated program. While ostensibly the SLS would still launch Orion to rendezvous with Starship, this would be an entirely superflous operation and I don't think this would happen in practice should Starship actually be developed. It's far more likely that Starship would perform the entire mission by itself imo.

In any case, Bridenstine has once again shown us his willingness to think outside the box and yet still keep Congress happy. In this way he has reduced the need for SLS while still throwing a bone to Huntsville, Alabama companies (Dynetics is HQ'd there and Blue Origin has opened a factory there) in order to ward off attacks from the powerful Alabama contingent in congress.

https://spacenews.com/nasa-selects-three-companies-for-human-landing-system-awards/

 

[AdamCrock]

Guess they need some booster rockets shipped to the ISS pronto ? I have an uneducated question : Is it possible to manufacture fuel on site ?

 

[uppi]

Guess they need some booster rockets shipped to the ISS pronto ? I have an uneducated question : Is it possible to manufacture fuel on site ?

In theory, manufacturing of small amounts of fuel would be possible (although probably very dangerous), but the ISS lacks the materials to make fuel in any relevant amounts. It is much more safe and efficient to supply it with fuel than to try to supply materials and manufacture it in space.

 

[hobbsyoyo]

On the other hand, the Moon has decent amounts of water that can be turned into rocket fuel and I think it would be much more efficient to do that than ship everything from Earth continuously. This is particularly true if you are trying to set up any sort of permanent base rather than just boots-and-flags missions that end after a couple of days. There will be a large upfront investment to get equipment to mine & refine the water relative to sending fuel but over time it will more than pay for itself relative to the expense of launching fuel freighters on a continuous basis.

Bridenstine has also announced an initiative called the 'Artemis Accords' which are meant to form international consensus on how in-space resources can be extracted and used and the environment affected by that activity. He's very forward thinking.

 

[AdamCrock]

I have a weird suggestion , what about harnessing helium-3 from solar radiation as a source of fuel ? Any future plans for that ? I think that would be mine priority if I were the head CEO of any space program. There is an untapped abundance of that particle in space.

edit: I realize it's as much a pipe dream as a fusion reactor, but it is nice to dream

 

[hobbsyoyo]

I have a weird suggestion , what about harnessing helium-3 from solar radiation as a source of fuel ? Any future plans for that ? I think that would be mine priority if I were the head CEO of any space program. There is an untapped abundance of that particle in space.

edit: I realize it's as much a pipe dream as a fusion reactor, but it is nice to dream

We don't actually know that helium-3 would make fusion easier because we don't have enough of it to try. But we think it would and the moon has actually been identified as a potential gold mine of it. He-3 is thrown off in the solar wind and minute amounts of it is trapped in the top layer of lunar regolith (dirt). The movie Moon was set in a mining operation where they were harvesting it for just such a purpose.

But before He-3 can be made valuable, we have to both prove that it works like we think it would in reactors and then figure out how to bring down the cost of launch enough that we can actually go out and get it from outer space in a cost effective manner.

 

[AdamCrock]

We don't actually know that helium-3 would make fusion easier because we don't have enough of it to try. But we think it would and the moon has actually been identified as a potential gold mine of it. He-3 is thrown off in the solar wind and minute amounts of it is trapped in the top layer of lunar regolith (dirt). The movie Moon was set in a mining operation where they were harvesting it for just such a purpose.

But before He-3 can be made valuable, we have to both prove that it works like we think it would in reactors and then figure out how to bring down the cost of launch enough that we can actually go out and get it from outer space in a cost effective manner.

If that obstacles would be overcome we should think a one step ahead and already lay claim on the Moon as it is. If it is a truly a He-3 "gold mine" than ... oh boy I can imagine an angry "Ivan" sayin' : "Our dog was here first ! So we're taking Your flag down and starting our own mine operation ! "

In fact (and please don't be angry) I got the idea of Helium 3 as a fuel from the movie "Iron Sky" I'm not a scientist, just Your average friendly neighborhood
interested redneck

 

[Imaus]

But it isn't a He-3 goldmine.

All He-3 is, as far as I know, a very efficient fuel for Fusion.

But 1) you need profitable fusion tech to begin with, 2) then handle d-t, t-t, d-t, or even water fusion ala 'generations' to make the technology more efficient, and then 3) make a big moon mining center that shovels millions of tons of regolith for a kg or so of He-3.

There's more of the thing on Earth, much more accessible, and we don't even have the tech to utilise it. It's why it's is DOA really, and it's just a bad plot token/mcguffin.

I think Iron Sky actually got around it because the Nazis mined it over a few years, so they were fighting for the depot and maybe infrastructure, but since they apparently nuked each other...whelp.

The moon will see space elevators and be a shipyard before it exports He-3 for money.

 

[AdamCrock]

But it isn't a He-3 goldmine.

All He-3 is, as far as I know, a very efficient fuel for Fusion.

But 1) you need profitable fusion tech to begin with, 2) then handle d-t, t-t, d-t, or even water fusion ala 'generations' to make the technology more efficient, and then 3) make a big moon mining center that shovels millions of tons of regolith for a kg or so of He-3.

There's more of the thing on Earth, much more accessible, and we don't even have the tech to utilise it. It's why it's is DOA really, and it's just a bad plot token/mcguffin.

I think Iron Sky actually got around it because the Nazis mined it over a few years, so they were fighting for the depot and maybe infrastructure, but since they apparently nuked each other...whelp.

The moon will see space elevators and be a shipyard before it exports He-3 for money.

Yeah but I was thinking the ISS can capture it from the Sun's radiation and convert it to fuel "on the fly" (as it radiates from the sun as it's own fusion back-product ? - we'll just fusion it more ? xD) so that the fusion generators keep running, without the need for mining of any kind

 

[hobbsyoyo]

There's more of the thing on Earth,

Is there though? This is news to me.

Yeah but I was thinking the ISS can capture it from the Sun's radiation and convert it to fuel "on the fly" (as it radiates from the sun as it's own fusion back-product ? - we'll just fusion it more ? xD) so that the fusion generators keep running, without the need for mining of any kind

The ISS is under the Earth's magnetosphere which would severely disrupt its ability to harvest the solar wind. Basically everything that comes off the sun is charged and it all gets funneled to the poles where it collides with the atmosphere and gives us the aurora. To harvest the solar wind, we'd need to get out into deep space.

 

[AdamCrock]

Is there though? This is news to me.


The ISS is under the Earth's magnetosphere which would severely disrupt its ability to harvest the solar wind. Basically everything that comes off the sun is charged and it all gets funneled to the poles where it collides with the atmosphere and gives us the aurora. To harvest the solar wind, we'd need to get out into deep space.

It's how "Northern Lights" are created right ? The Sun unleashes an ungodly amount of radiation , which is than confronted by Earth's magneto-sphere and come into reaction with all the particles there - that is what makes "Norther Lights" so beautiful and magnificent. All that "sun ray" particles come into a chemical reaction with our atmosphere I bet some bald Odin-or-Thor-like xD Viking once said - one day we will be able to harness that light and be like the gods, travelling through that void, we will fill the night sky with awe and wonder and our legacy will be the rainbow .... ehhh, the poetic side of me is surfacing

edit:

Ahhh....simply beautiful ...

 

[hobbsyoyo]

Basically. It's ionized hydrogen and helium in the solar wind that is the major component that causes the northern lights, not radiation. Though I guess a plasma will tend to ionize things it comes in contact with so maybe it can be considered a type of radiation?

 

[AdamCrock]

Pseudo-Philosophical rant (of sorts) :
Actually we want to be like the rainbow - all the spectrum of light , we want to be everywhere , do everything and as cold reality informs us , we can't be like the light - be everywhere. Our flesh and bone particles cannot be in the spectrum of light..... Damn I sound like one of those unsavory cult guru's but I do not want to sound like those worship-my-turban-dot-com's :/ . I just merely realized we're just a flesh and bone monkeys unable to be the light , wanting to be something more, which is quite impossible.... unless You can warp me to a speed of faster than the speed of light and than reassemble me like an IKEA furniture set I was before, there's no hope we will ever reach an exo-habitable-planet like Earth (there are more and more discovered but the distance is staggering) Well, on the plus side, we're one of a kind ! Maybe there are (I am sure there are - with infinite numbers comes an infinite number of possibilities which makes the claim of aliens a certainty , rather than just a probability) being that have transcended the boundries of flesh and bone and can be like the light ?

 

[r16]

good , the thread owner is back . Can keep up , with additional eyes on the wellbeing of the thread , now that the majority of moderators not 100% tech qualified to deduce merely spam or quality trolling .

accordingly , we have lranians launching a satellite , the head of US Space Command calling it a joke (by r16 words) and internet people correcting him but also discovering that it was obviously bought from a company in California , in the same batch with the Mexican satellite . We have Chinese bombing West Africa , the same pipe being photographed from various angles in crowded streets , because the same Chinese also failed with the coronavirus and because . And who knows , it might have actually happened too , rocket launcher pieces unburned in the air making it to the other side of world , to Africa , where China was a threat even in Clinton days . Also , US Space Command because it turns out Americans were deceived by their erswhile allies , aliens and the Fourth Reich in Antarctica so they have found new allies , a full 10 feet tall blonde on the book cover shaking hands with an USAF general or whatever so this is why US Space Command was declared and soon America will show its saucers , soon , really soon . Don't know whether it is good or bad that the tablet lacks software to read the books trawled off the web .

and yes , the thing the world actually wants to know . What , after ı have been banned again , elsewhere , with actually doing nothing . Especially in view of the things ı could be trusted of being capable of knowing . Will be remembered , naturally , making sure it was a solid track record , of maintaining company reputations when even they were attacking the very same companies . And reputations . Everybody UNDERSTANDS me and everbody in the aviation world remembers my weird pals (in a Turkish language only webforum) would troll Bill Gunston as a regular thing and he was much better in defending himself in person . Sad , man , really sad , he at least had stuff as in hardware to sell .

 

[uppi]

We don't actually know that helium-3 would make fusion easier because we don't have enough of it to try. But we think it would and the moon has actually been identified as a potential gold mine of it. He-3 is thrown off in the solar wind and minute amounts of it is trapped in the top layer of lunar regolith (dirt). The movie Moon was set in a mining operation where they were harvesting it for just such a purpose.

But before He-3 can be made valuable, we have to both prove that it works like we think it would in reactors and then figure out how to bring down the cost of launch enough that we can actually go out and get it from outer space in a cost effective manner.

So He-3 myth time again:
- We know that He-3 would make fusion harder instead of easier. The D-He3 reaction requires temperatures about 10 times as high as the D-T reaction and only generates 5% more energy. So you are looking at 1 billion K instead of 100 million K and this makes the big challenge of fusion (confining plasma at these temperatures) much harder.
- We have enough He-3 to try if we wanted to. He-3 is a waste product of nuclear reactors and nuclear weapons in small amounts, so there is some production on Earth. The current production would not be enough to power a continuously running fusion reactor, but it is certainly enough for research.
- He-3 is the decay product of T. So if you have enough T to power a fusion reactor (which can be bred from Li), you wait a decade and have enough He-3 to power a fusion reactor
- The big advantage of D-He3 fusion is that you produce protons instead of neutrons, which can be controlled much easier so that you can avoid bombarding the reactor with neutrons. This could mean that a reactor running on He-3 would take much less neutron damage, could last much longer and would be less contaminated. This could mean, that if you manage to build a He-3 fusion reactor, it could be much more cost efficient than one running on T. But to actually build one would be much harder

So if we manage to get D-T fusion to work and then get D-He3 fusion to work and figure out how to cost-efficiently run a fusion reactor and haven't switched to renewable energy by then, then it might be profitable to mine He-3 on the Moon and bring it back to Earth. But it is optimistic to hope that this will happen in 50 years.

 

[r16]

but it surely allows an US President , Dabya by name , to offer exclusive rights to mine it on the Moon , in return for not interfering in the bloody carnage in lraq (and future operations in Syria and lran) on the scale that Kennedy offered by going to Moon by the end of that decade , because the people of Moses and all that silly bunch of notions that could be produced by the smart then and now . Noice , as they say over the web , considering Dabya didn't have a shoelace of capability to occupy and control the moon as well . For those aerospace people elsewhere who can not understand unless it is spelled for them ? Dabya wets himself offering fake mining rights over a fake theory for real gains , because that was Kennedy had done , as far as Kennedy thought .

 

[hobbsyoyo]

So He-3 myth time again:
- We know that He-3 would make fusion harder instead of easier. The D-He3 reaction requires temperatures about 10 times as high as the D-T reaction and only generates 5% more energy. So you are looking at 1 billion K instead of 100 million K and this makes the big challenge of fusion (confining plasma at these temperatures) much harder.
- We have enough He-3 to try if we wanted to. He-3 is a waste product of nuclear reactors and nuclear weapons in small amounts, so there is some production on Earth. The current production would not be enough to power a continuously running fusion reactor, but it is certainly enough for research.
- He-3 is the decay product of T. So if you have enough T to power a fusion reactor (which can be bred from Li), you wait a decade and have enough He-3 to power a fusion reactor
- The big advantage of D-He3 fusion is that you produce protons instead of neutrons, which can be controlled much easier so that you can avoid bombarding the reactor with neutrons. This could mean that a reactor running on He-3 would take much less neutron damage, could last much longer and would be less contaminated. This could mean, that if you manage to build a He-3 fusion reactor, it could be much more cost efficient than one running on T. But to actually build one would be much harder

So if we manage to get D-T fusion to work and then get D-He3 fusion to work and figure out how to cost-efficiently run a fusion reactor and haven't switched to renewable energy by then, then it might be profitable to mine He-3 on the Moon and bring it back to Earth. But it is optimistic to hope that this will happen in 50 years.

Excellent write up, thank you.

On the point about us having enough HE-3, do we have enough that we can access in a cost efficient manner? Putting aside the efficacy of its utility in reactors (assuming it was this miracle substance that would make fusion easy), could we actually get it from sources here on Earth more cost effectively than mining it on the moon?

 

[uppi]

Excellent write up, thank you.

On the point about us having enough HE-3, do we have enough that we can access in a cost efficient manner? Putting aside the efficacy of its utility in reactors (assuming it was this miracle substance that would make fusion easy), could we actually get it from sources here on Earth more cost effectively than mining it on the moon?

Good question. Neither dedicated mass production of He-3 on Earth nor mining of He-3 on the moon have ever been tried, so any cost estimate for either would be wild speculation. Especially if we assume that an efficient fusion reactor has been invented, since then most efficient way to produce He-3 might be in D-T fusion reactors.

My gut feeling would be that if we wanted to deploy He-3 fusion on a grand scale (requiring tons of He-3), mining on the moon might actually be the more cost efficient source. But my gut feeling is also that we are at least 100 years away from that point.

 

[r16]

hmppf , boring day . So much that ı have decided to make some splendid defence ... against mean r16 ...

Spoiler :

it starts as a good question . The Western Allies were surprised with Panther being so much around . As "King's Tiger" by about 1943 , a theoritical study whether America had to develop an heavy tank , because they would place extra demands on ships being ordered in 1941 and 42 and Admiral King had asked what the Germans might field in 43 or 44 , it had to be in ones or twos , seen once or twice during the entire war . lnstead of being standart equipment of Panzer divisions . American tanks didn't have much capability to face it head - on , the war to be win or lost with the Sherman ... Yes , there was to be a solution and yes , it failed on simple physics and adding that to a certain desire to prolong the war and you have to read memoirs of Russian servicemen to be surprised to see the spent Wehrmacht could still manage to make Russians , well , fear .

so , what if Allies had anti-tank missiles ? No footage or something but the Germans were developing wire guided B-17 killers and it's said a development or modification was used against Russian tanks . Yours idiotly says hundreds . Because Bill Gunston says that somewhere . Yours idiotly might have gone scott free , but no , he can't shut up , so he also says the Hungarians had their own design and might have used it as well ...

the science of History demands proof . Documentation , and also your name and track record , to convince you are not making anything up . lt is called the discipline of the thing . Names are important and all the respect for that , too . And , yes they are historians down there , many writing books for a living , too . ı have neither , no documentation , no name . ı say so . But the thing revolves around Gunston , world famous aviation writer . So famous that you could make the day of any Russian engineer in the airshows of Paris or Farnborough with giving him a copy of any book Gunston wrote , this is real and has been reported in the aviation magazines . Also he had ties to lntelligence world and at times he would really say things that went against the conventions . Of tech or history . The guy hints somewhere that his father was responsible or something about -at least- the safekeeping of German records on lR dedectors during WW ll and had truckloads of them and nobody ever bothered to read them for quite a while . No surviving documents , no footage ? Do not ever dismiss the German ATGMs in WW ll , you might just find them someday somewhere ...

the danger ? They have this thing about the super duper Nazis inventing everything . Fully justified , totally correct , entirely acceptable . This should get into a thing about how Nazis were 10 years ahead , it was last week or a fortnight ago ı read about the Civ modder that will not re-release a WW ll mod , because some jerk might add the picture of Adolf in it on his own . So , a researcher guy can claim it would be interesting to compare the blueprints of the German weapon with the ones of the French , British , American and Russian designs of 1950s or 60s . He can , he researches . ı can't ? Not offended . Haven't said anything about the "stones" .

now , gotta remember the German nuclear bomb ... thing . The scientists were all locked up in a British manor or whatever and the place was bugged and when Hiroshima was nuked , all the Germans were astounded and they debated it and the tapes prove they were years behind . History teaches us so . Except Nils Bohr made it sure that his one time student got it , understood fully . That the Americans were fully staffed and they would neither need the Germans nor let them free so that they could be grabbed by anyone , namely the British , French or Russians . So , the leader of the German effort made sure that his opponent in wartime understood that opponent was sabotaged and hindered at every turn by the leader , for a good reason . They already knew what the camps were for . Then they had a perfect job . And had to stand guard for a guy who had discovered he had lived years of a lie .

living a life of lies is much better then living a life of lies , with a feeling of blood on one's hands .

much writing and mimicking to convince the guy that the leader had managed to call for airstrikes and moved the opposition team out of the crosshairs in the right moment , too . Fully supported by the Opposition . The Opposition team was indeed a threat to Democracy and Liberty and whatnot in the early 1940s . Being 100% loyal Germans . Yet , science was their food on the table and they felt Germany was an utter mess for years to come and they did look for jobs , by talking so much on the "stones" . Am no real science guy to explain what the hell , but all the books do hint some sarcasm at Germans talking silly , instead of covering their heads in shame , being defeated so utterly by Anglosaxons , despite History still not been able to write Fuchs gave the bomb to the Russians and the Brits after like doing it for the Americans . See , r16 never claiming anything like Hellfire in action in 1945 , blowing JS-3 turrets off the hulls . An accident . And we can always ask whether they ever felt ashamed at Texas lnstruments when they were doing the original LGBs . Original bombs having fixed control fins and stuff while the Brits discovered the "current form" in Ruhr 1946 ; Ju-88 has a small bomb bay and needed all sorts of drag reduction to survive . And yes , a lot of research , for when you are so grossly outnumbered , the idea that every bomb should count becomes quite urgent , richtig ? Even if it was still radio command for the Luftwaffe . USAF people looked at the proposals , and the calculations of how many they could fit on the B-52 . They said "no" , what were you expecting ?

see ? A glorious thing ! Now that the world would say anything . When Air lnternational was Air lnternational ? This being a challenge to publishers ? Was there , reading the actual paper magazine in my hand as month over month they taught the audience that F-18 was uber super to F-14 . And Footpad yet to become F-35 uber super duper hiper omega hipper to F-18 . Hollywood not permitted to film Top Gun ll for more than 30 years and blogs hint they still needed a Tomcat to be in it , because guess what , somebody has failed to give a radius of a full thousand miles to the F-35 . Wait , was that in kilometers ? Germany has to buy F-18s to stop Poland and the Baltic Republics doing something silly , because deterrence because surprise , surprise ! Tests have not advanced fast enough to clear B-61 on the F-35 . Come on , who is to going lay down nukes in this age ?

or the super irritating attack on the Jaguar , implying it wasn't running and would loose to the F-5E . How about improving that ? British writers of course blame the Japanese stealing and banditry and pirating the Jaguar to make the stupid F-1 of Mitsubishi . Except Lord Vader says when America was paying the European plane makers , you know , like 1950s Breguet offered to do stuff and it would go head to head with the '104 and guess what it looks like ... And wasn't it comforting to the Chinese and Russians and all Eastern Asia for their nice and polite neighbours the Japanese to be building lesser ? No , the Japanese Constitution could not be revised for anything so silly and no , Lord Vader was not among those who cried on the ships when American pressure made the fleet return from action in Cyprus 1967 without action and yes , this country would either fight or ... And the prepations went ahead and the Yugoslavians and Romanians had the idea to make a 1950 style Jaguar and they were like turtles and half the plane was imported from the UK and they still managed to have the maiden flights in 1974 and nobody can ever make much sense of a generalized claim of how Oaro/lAR-93 could be a "replacement" for a F-5E . And yeah , Gunston would leave no trace of his spats to sell straight or new Adour engines or 30mm ADEN guns . This , my friends and non-friends , would fry the brains of plane-minded boys allover the Anglosphere ...