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Comment by superkuh | Hacker News Reader

It's a shame that the lunar gateway is useless and itself a jobs program like SLS. Since NASA decided not to fund the version of the asteroid retrieval mission (ARM) that included de-spin there are no near earth asteroids that can be brought back to the proposed space station. All it can do is uselessly orbit the Moon, getting full cosmic radiation dose instead of less than half in Earth orbit in the magnetosphere.

In terms of resources the moon itself only has water. But it's down in a difficult to access gravity well. There's no nitrogen. Far, far, better would be fully funding ARM and starting to despin and drag asteroids to the lunar gateway for study, resources, and eventually living space in space protected from radiation and, if you build sub-surface tracks, enough acceleration to live normally.

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Lunar gateway is a first space station that will not be orbiting Earth. While current approach is inefficient, I assure you the challenge of building, launching, and operating such a craft will definitely push overall space capabilities further.

Maybe. But what does that get us? We'll never be a spacefaring species, the universe is way too big (we can't even explore our solar system in any meaningful way) and energy requirements for faster travel are simply too high. Not to think of all the issues with spacetime at fast speeds.

There are tons of serious problems to solve here on earth, no need for another huge waste of money.

Not everyone agrees with you, which is why humans are capable of a wide range of behaviors and investments.

If we didn't have interest in space, there would be no SpaceX, Starlink, Mars rover, planetary missions, etc.

I personally think we're about to reach the terminal generation in 100-200 years with advancements in ML, and we won't be worried about sending human bodies anywhere. Just engines, sensors, and computers.

I know - you would think that with sixty-five whole years since the first satellite launch we'd be able to meaningfully explore our solar system already. It only took a few thousand years to fully map and explore the Earth's surface and you'd think exploring multiple planets and billions of miles of space would be 100x faster than that.

That money could be much better spent, like on tanks we will never use.

We have explored our solar system, we’ve sent multiple probes to most planets, done a flyby of Pluto, landed on Mars, Venus and several asteroids, driven multiple rovers on Mars. Put rovers and boots on the ground on the Moon. We’ve extensively mapped almost all the solar system.

> We'll never be a spacefaring species, the universe is way too big (we can't even explore our solar system in any meaningful way) and energy requirements for faster travel are simply too high.

I can state flatly that heavier than air flying machines are impossible. — Lord Kelvin, 1895

https://www.xaprb.com/blog/flight-is-impossible/

That's very true, but you'd have hoped they could have optimized along both dimensions at once - push forward capabilities, and achieve some useful external outcomes.

How do you get enough fuel to the asteroid to bring it back if even sending a 'measly' rover to Mars is a multi-year endeavor. Asteroids weight a lot more than a rocket and you need to change their velocity by the same amount

https://www.space.com/20610-nasa-asteroid-capture-mission-in...

This is the low cost version of the ARM program that funding was chosen for. It is kind of marginal because there are literally only 3 near earth asteroids with little enough spin that this design would work.

Yes, but you don't need to use chemical propulsion for 100% of the needed energy -- just a well-timed and well-aimed change in angle to slingshot it off of a gravity well.

The real answer: It's entirely beyond our capabilities and not achievable at all.

The energy cost of changing something's orbit is not just mass times distance, otherwise launching a 1 metric tonne probe to Mars would have been impossible. Thanks to orbital dynamics, there are a lot of opportunities to get huge bang for your delta-V buck.

Not true. Well timed gravitational slingshots have been used on many existing missions. e.g. https://en.wikipedia.org/wiki/Parker_Solar_Probe

Of stable masses capable of analysis in advance to their mechanical properties under thrust. Asteroids are known solely by their orbital elements and we have literally no idea how the specific mass works as an aggregate or bonded entity, under load or stress.

You can line up a slingshot with a very low rate of acceleration, though.

Yes. I probably overstated my case. How quickly would that deliver a benefit?

It could take years for each mission, but of course at industrial scale you could have a continuous delivery queue and processing each asteroid could provide months or years worth of material. Think of each asteroid as a new mine being opened up. These initial missions are just proof of concept to test out techniques. You have to start somewhere.

So strap a rocket to one and find out. If it doesn't work grab another.

Having created literal mayhem in an unstable orbit of uncounted masses, ie for a giant externality. Next flight up, don't be within a large amount of space nearby in orbital terms, without care. (Maybe. Im not a kerbal person or an astronomer or flight engineer. This is a precautionary question to risk and to whom it applies)

Asteroids are very far apart from each other on the whole. Kicking one off in a different direction with a rocket isn't so different from a change in direction from a (rare) collision, except that it will almost certainly only affect one asteroid. ~25% of all the mass in the asteroid belt is the dwarf planet Ceres, which is only 0.0128 the mass of our moon. https://en.wikipedia.org/wiki/Ceres_(dwarf_planet)

There’s a vast amount of rubble flying about any which way up there already. About 100 tons of rock and dust enter the earths atmosphere every day, it’s just that space is so vast the chances of any of it hitting a vehicle are quite small.

The asteroid is the reaction mass. Send a solar collector and a rail gun sled that fires bits of asteroid really fast backwards.

That's a massively complicated endeavor and would require a lot of knowledge we don't have at the moment principally zero G mining and remote robotic assembly (time lags will mean it'll have to be very automated).

And reliable railguns.

That sounds like experience we’ll never get if we do not even make the attempt.

Eventually, it's not the first step you take though.

Forget railguns; an automated burger flipper could launch chunks of rock at escape velocity.

The faster you can accelerate them the more dV you get out of each chunk so you want to get them moving as fast as possible. If you're barely tossing them off the asteroid you might need to throw away a majority of the asteroid's mass to move it into Earth's orbit.

ARM was going to bring back a moderate sized asteroid the size of a small car or so. The reason this works is that there are no deep gravity wells involved. The delta-v needed to move things over long periods of time is feasible if difficult.

To be explicit, the ARM mission propulsion bus, canceled in 2017, is now to be the main component of the lunar gateway program. But it's like putting the cart before the horse with no intention of getting a horse ever. All this talk about lunar gravity well exploration is just sour grapes.

https://en.wikipedia.org/wiki/Power_and_Propulsion_Element#A...

That mission is targeting something the size of a washing machine not a car. Something around 5,000kg is reasonable, but asteroids are denser than your thinking.

How much metals are in this 5k kg rock?

That’s dependent on the rock. An metallic asteroid would be something like 80% Iron which is 7,873 kilograms to the cubic meter.

However, the limitation is mass not volume so while an asteroid 1/3 that density might be chosen it’s still going to be fairly compact.

A simple first step done sooner is better than a complex first step done later. Also, seems like there's a lot to learn about space habitats just by building another one - we haven't made that many yet.

11?

https://en.m.wikipedia.org/wiki/List_of_space_stations

Most of those things were largely too tiny to count as much more than practice runs for building actual space stations - in that list, the majority were less than 1/30th the size of the ISS - did you see the column on the side listing the cubic feet of space in them? 100m^3 is a ~4.5m box.

So yes, we've put 11 space stations in orbit: only if you count a one-room flying can as a space station. I think we have a few more practice steps to go before we start hollowing out asteroids as GP was suggesting we do next.

>In terms of resources the moon itself only has water

It has vast amounts of Helium 3. This could potentially be very valuable. https://en.wikipedia.org/wiki/Helium-3#Lunar_surface_2

As there are no commercial fusion reactors using helium-3 or not. Why would we believe this resource has direct value within the next 5 decades?

Sci-fi author Charlie Stross had a wonderful take-down of He3[1] a decade ago. It's alas not very technical. The short of it is that there are no reactors, if we do make them they are going to be insanely fantastically hot (a billion degrees), there's only ~10 parts per billion (according to your wikipedia link) on the moon & mining that will be hard, and then we'd have to transport the stuff too.

I'd read something else about the challenges of reactor design, but not sure what it was. I haven't been enthused about He3 since. I feel like the one interesting use would be a Project Orion / Nuclear Pulse Propulsion system, but wow, boy does that seem like an expensive way to do propulsion: what's the use case?

[1] http://www.antipope.org/charlie/blog-static/2010/08/moonshin...

That's science fiction with no grounding in reality. You may as well be going on about transporters and transparent aluminium.

Every time a Moon mission comes up, Helium 3 gets trotted out, but it's just absurd.

For one, billions of tons of rock would have to be mined to extract any reasonable amount of Helium 3. Even with heavy machinery and robotic miners operating 24/7, this is a stretch.

But much more importantly, Helium 3 is utterly useless. It was proposed as one possible fusion fuel but then a much cheaper alternative was developed almost immediately: breeding the required fuel from a blanket of Lithium.

Last, but not least: There are exactly zero fusion power plant operational on Earth right now. There will be exactly zero commercial fusion power plants operational on Earth for at least a decade, no matter what new technologies are developed. At the current pace, according to current plans (e.g.: ITER/DEMO), there will be one (1) power plant generating a trivial amount of power staring in 2048. Likely well into the 2050s there won't be many more.

So to summarise mining lunar He3: We should spend trillions of dollars digging up the Moon for power plants that won't exist for three decades and don't need need the helium anyway.

It reminds me of an old saying: "if we had some eggs, we could make ham and eggs, if we had some ham."

If my grandmother had wheels, she'd be a bicycle.

The little old lady from Pasadena certainly has wheels, but she’s no bike

https://en.wikipedia.org/wiki/The_Little_Old_Lady_(from_Pasa...

I just find those timelines hard to believe. We just condensed a 10 year vaccine development and rollout process into 1 year, and that was mostly because of human trials. The reality is that nobody is interested in funding such an effort for fusion.

Hard problems aren't comparable in that way. The vaccine timeline was "shortened" because the timeline doesn't include decades of foundational work in molecular biology that made it possible for the vaccine formula to be determined within days of the virus' genome publication.

In principle, it is in the best interests of every nation on Earth to get together and organise along the lines of the famous Manhattan Project to develop fusion. Throw money at it like we've been throwing at COVID. Multiple teams working in parallel in a race to solve the problem, like the vaccine development teams were. Eliminate the red tape. Cut the bullshit. Get on with it.

The payoff would be worth it a hundred times over. Not just because of cheap, clean energy, but also because the earlier we start weaning ourselves off of fossil fuels, the better.

But did you notice my choice of words? I said nations, not governments. Governments do not represent their nations. They represent themselves. And they are made up of a small number of greedy, self-interested, mostly corrupt individuals looking out for their own personal benefit. They benefit from bribes (coughconsulting jobscough) from their "partners" in industry. The oil industry. The coal industry. The gas industry. Not just mining! Even power generation industries have a vested interest in delaying fusion as long as possible.

There is no fusion industry yet, and non-existent industrialists cannot pay bribes.

This is the essence of why governments are disinterested in the future. They're only interested in the bribes they get in the here and now. Oh, I'm sorry. "Alleged" bribes, I mean... perfectly legal donations.

Worse, the scientific bodies involved in the nascent fusion industry, like ITER, have become cancerous. They exist now only to justify their own enormous scale. A growing bureaucracy that benefits only from its own size, not in achieving its goals. Hence the plans out to 2050. The longer the better. Got to think about all the project managers that want to reach retirement age and start collecting that pension without ever having to actually deliver.

There is no possibility of a Tokamak ever producing one commercially-viable erg of energy. It wouldn't matter if every nation on Earth joined in. The entire concept is useless. Even with absolute success at every step, such energy could never get below even 10x the cost of solar + wind + storage, even ignoring all the $billions already poured in.

There is exactly one reason we spend $billions every year on Tokamak: it is a jobs program for high-neutron-flux physicists, to maintain a population to draw on for weapons work.

That is not to say fusion is itself a dead end; just that Tokamak is stealing the funding that could otherwise develop practical fusion power. E.g., the FRC DFD project shows every sign of near-term viability, but is starved for the small amount of money that would take them to fully practical power generation and also spacecraft propulsion.

The project is in "Phase II" development under NASA, and needs just $50m to get to a viable prototype -- pocket change for the Tokamak club.

Precisely. Instead of one sunk cost fallacy after another used to justify ITER and its enormous bureaucracy, there should be a billion each thrown at a couple dozen likely alternative ideas.

I read a paper recently that basically said that the best bang for buck is to just work on better superconducting magnetic tape. Stronger fields make everything better, and the scaling law is cubic!

Even if such a tape is developed but doesn't lead to fusion, we'd have better MRIs and DC power lines as a side effect, so it's not even wasted effort!

Even the best HTS tapes won't make fusion competitive. Limits on power/area through the first wall guarantee fusion will have bad volumetric power density compared to fission, even at high magnetic fields.

It is my understanding that FRC fusion could make good use of HTS tape.

We can still say that no amount of HTS tape, or of anything else, will ever make Tokamak hot-neutron fusion competitive. But that is not a reason to abandon HTS tape development.

> The reality is that nobody is interested in funding such an effort for fusion.

Go check out the money being spent building ITER. I won’t spoil the surprise here, just to say if it doesn’t make your eyes water there something wrong with your tear ducts.

https://en.wikipedia.org/wiki/ITER#Funding

Even if we threw as much dollar into fusion as we do on military, it won't work. Because we're not lacking money but understanding.

> Transparent aluminium

Good sci-fi always has an eye towards the future - we have transparent aluminium now. The whole point of science is to push the boundries of our knowledge.

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

If you postulate a still non-existent fusion reactor, and then postulate an enormous industrial lunar mining program- 150 tons of lunar regolith gets you 1 gram of He3- this might, might, might work out. Most people who crunch the numbers think that this will never be sufficient in and of itself to justify a lunar program, it only makes economic sense if it can piggyback on top of a program that exists for other reasons.

If you want helium3, seawater is probably a better source than the moon. The difference between 150 tons of lunar rock and something like five times that of seawater is probably a wash, even ignoring the expense of gravity wells.

There is no significant amount of 3He in seawater. Perhaps you were thinking of uranium?

Deuterium and Tritium probably.

There's very little tritium in seawater either (and it was mostly put there by hydrogen bomb tests.)

Helium-3 coming from active seafloor vents has something like 10x (to in some locations 30x) the ratio of 3He/4He in the atmosphere. This is so consistent that it is often used as a way to detect underwater vulcanism. Yeah, it's still an order of magnitude less than in the lunar regolith, but we have lots of experience handling seawater at scale, and we have zero experience handling rocks in 1/6th G at scale, so I would probably bet on it taking a long time for the lunar mining to get to the same effectiveness as the seawater handling.

> a jobs program

Why is funding into technological advancement a "jobs program." We don't call research a jobs program. Rome wasn't built in a day.

Because it was selected on the basis of what spending it could justify (in particular, that it would give the SLS something to do), not on the basis of the value of any technology produced.

I’ve come to see this as a feature not a bug. To get a significant amount of money from elected officials there has to be a there, preferably their district. SLS was the giant scaffold that allowed for the effective seed of commercial resupply missions to occur and grow. Without SLS’ distributed network of Government friendly contractors and contracts all lined up in an immaculately conceived waterfall the focus would be on the commercial efforts which have to be run a different way to get better results. Imagine instead of Joe Rogan, Musk is spouting off to some committee of crusties. That wouldn’t be pretty, and success means avoiding that conflict in world views by funding SLS. In some ways it is kind of like funding a semi-fake cathedral in order to attract and develop the bazaar you really want.

It's a feature if you're feeding at this particular trough. It's not a feature for the nation as a whole. It leads to money being squandered. The goal should be to benefit the nation, not maximize a budget line.

Is the effort to build a scaffold squandered since it is used to build something but is not the thing being built? I'd rather see economically sustainable off-Earth enterprises built without a scaffold but I'm not so loss averse to take nothing over something.

If the technological advancement is funded by a private entity (whether or not for a profit motive, there needs to be no such justification). If it's public sector you need to at least come up with some public benefit excuse for it, jobs program is a bit of a steel man for the political funding of a science program. If you want your science to be free of that entanglement you should be figuring out how to fund more things like Glynn research ltd.

We're at Beta and you're talking about features for version 10.0.

Let's ship first.

Well, maybe SpaceX ends up providing free near-earth Starship operations for an advanced ARM.

Basically, launch a probe that goes to the asteroid, spins up to match, collects it in a net/blanket, and maneuvers to meet up with a Starship in an highly elliptical or maybe lunar flyby orbit. The Starship would rendezvous, match spin, load the cargo in it's payload bay, and proceed to de-orbit.

As long as you engulf the asteroid, the spin shouldn't be more than a minor nuisance (e.g. pulsed thruster firing control systems, reinforcement to endure centrifugal loads). You might even be able to de-spin on your way back to earth.

My understanding is that Starship is capable of landing with full 100+ t payload, thanks to the aerodynamic reentry. Also, with no passengers, it could easily spend a few orbits getting the apoapsis from "almost Earth-Sun L5" down to a LEO before re-entry.

Absolutely disagree, and I think the waste majority of space nerds do so as well.

ARM was a mission literally designed so Obama so NASA would have something to do with SLS and Orion. It was a pretty terrible mission that basically nobody wanted except the president.

The actual ARM that they settled on would only pick up a small bolder from an asteroid and bring it to earth orbit. Not large enough to live in, not even close. And not even useful for resources.

Water is by far the most useful thing you can find, and its what makes everything else possible. The moon has a huge amount close to each other. Almost every expert I have heard talk about is, think getting water from the moon is the best way to use space resources early on.

>In terms of resources the moon itself only has water

This is completely false. Just FYI.

There is lots of different useful materials on Mars.

Check out this video by former NASA engineer who has work on in Space manufacturing for many decades:

https://www.youtube.com/watch?v=9-RTBGnzNks

You can literally build solar panels, batteries, and many other things with martian resources.

It was a test of:

* Asteroid redirect tech in case of, you know, a dinosaur killer coming your way.

* Asteroid harvesting.

It would do some gravity stuff that now other missions are doing already.

It would have picked up a single small bolder and brought it to LEO.

Non are relevant for resource mining.

> and eventually living space in space protected from radiation and, if you build sub-surface tracks, enough acceleration to live normally.

Can you clarify what you mean by that please?

What protects from radiation?

What are "sub-surface tracks" and the "acceleration" they provide?

I don't know exactly what the OP means but putting something big and sold between it and the sun is a good way to limit radiation. Maybe the moon in this case?

The earth's magnetosphere protects from radiation.

They're talking about living inside an asteroid that has been moved to the lunar gateway. You can imagine a looped track dug inside, to provide simulated gravity. I don't think that's very feasible, I prefer the "Islands in space" idea from Gerard O'Neill. To provide artificial gravity.

https://en.m.wikipedia.org/wiki/O%27Neill_cylinder

That must be a giant rock that you must carve an internal loop out of.

And then, how much energy would it even take to spin such a huge rock? I think you’d need a new exotic propulsion system just to rotate it. Maybe nuclear or a sustained ion propulsion.

Sorry I wasn't clear.

Being beneath the surface provides radiation protection.

Specifically by digging out tunnels beneath the surface of moderates size asteroids, putting down butyl ruber tubes, and laying tracks within. By having the cars on the track go around the curved track an artificial gravity is induced.

But you can stop the space train cars, step outside, and there's no deep gravity well to make getting things to and from there so expensive.

----

I'd also like to make it clear that the Asteroid Retrieval Bus, the mission that was canceled, is the reason the lunar gateway concept exists. Having the lunar gateway but not asteroid de-spin and retrieval is putting the cart before the horse without intentions of getting a horse.

https://en.wikipedia.org/wiki/Power_and_Propulsion_Element#A...

>The Asteroid Redirect Vehicle... ...mission was cancelled in early 2017 and the spacecraft's propulsion segment became the Power and Propulsion Element (PPE) for the Deep Space Gateway, now known as the Gateway.

For starters, the moon has helium-3, which is incredibly rare on earth and would be very useful for nuclear fusion should we ever figure that out.

The process of mining helium-3 won’t be cost efficient for a long time. It’s an overhyped material that requires sifting through kilometers of lunar regolith for grams of H3

It’s not the destination, but the journey.

Mining for He3 would require all kinds of new technology to be invented. And necessity is the mother of all inventions.

For sure and I don’t agree with the GP that the Lunar Gateway is useless. Even it just existing and people going to and from the moon will breed new systemic knowledge and inventions we otherwise wouldn’t have or need. Plus having a constant group of people living in orbit around another celestial body is just sexy in its own right.

The moon is a body with enough stuff to sustain heavy industry, is easily accessible from the Earth in a few days all the time, and a gravity well weak enough that a space elevator, or even a rail gun, can be build with todays material science.

Long term all of those make it a very valuable place for exploring the rest of the solar system.

Usually the goal of having source of anything outside Earth is to use it to build (spacecraft, stations, etc.), not to bring it to Earth.

The Moon gravity well is weak but still significant.

On the other hand you could catch an asteroid and bring it back to Earth orbit and exploit it here or even completely remotely, by automated means.

But also, we don't have the technology to do that, either.

Sure we have. We have rockets to get there and we have nuclear reactors to vaporize stuff. Asteroid itself can be used as reaction mass.

The amounts of energy can be as little as you want if you go far from the sun where orbits are very slow and very little energy needs to be used to move an asteroid in any direction you want.

This is pure sci-fi. We don't have the technology to travel within our solar system in any reasonable amount of time, let alone to bring back and mine an asteroid.

Again, that is simply not true. The technology already exists. Need a modest rocket that can bring a nuclear reactor to an asteroid and heat up part of its mass as exhaust for a long enough time to deflect it by couple cm/s to maybe 1 m/s.

The only thing you need to do is to be patient. A lot depends on how greedy you are, if you want a smaller one it gets exponentially easier.

Just read this 10 year old report: https://space.nss.org/technologies-for-asteroid-capture-into...

Did you read the "Note" at the top of that link? From that it's clear that this is a many-decade project: if it had been started in 2011, it would only be partially done by 2030. That would not be the "reasonable amount of time" requested by parent. Technology will improve, and eventually all sorts of things will be feasible. More reasonable plans can be hatched at that time.

There is huge difference between multi-decade projects and "pure sci-fi" or "impossible".

"Reasonable" is subjective to define, but there are many multi-decade projects running right now so I don't think of multi-decade projects as unreasonable.

Things like sending man to the Moon or building Space Station would have been deemed "pure sci-fi" with the approach of the parent commenter.

People said the same thing about reusable rockets only a decade ago. Now they're common place.

All the things above are fully realizable in the coming decades, they are not in the realm of science fiction what so ever they are merely engineering problems.

1. Define “reasonable amount of time”

2. Define “technology”

The meta-technology of R&D and socio-economic programs that will make these things happen exists and gets better every day. If a method to perform the needful does not exist, it will given the right conditions.

How exactly would you use a nuclear reactor in space to melt stuff? I assume it would be indirectly right?

On earth, the nuclear reactors are radioactive rods that heats up water, to create steam, to spin a turbine, to create electricity. This is like a 5 stage process to indirectly generate electricity. But all the intermediary products are now radioactive.

So in space, I assume you can use the same steps to generate electricity, and then use the electricity to run a furnace, to heat up the minerals to melt it into pure metals.

Or is there some other process of using the nuclear radiation directly in space?

On Earth, nuclear reactors are complicated because they must be safe.

But really, reactors are extremely simple. For example, on Voyager missions the it is just a hunk of metal that is constantly hot.

https://en.wikipedia.org/wiki/MHW-RTG

You then do with that energy whatever you want.

You can use part of it to power electronics and actuators, part to melt a piece of asteroid and part of it to convert it to ions and send whichever way you want.

An RTG is not the same sort of thing as a regular fission power plant. I don't believe they are efficient or high powered - they are just useful as batteries that last a long time without maintenance or recharging.

Also, RTGs have been used on earth, contrary to your implication they are only in space for safety reasons. Russian equipment in the arctic, for instance, has been powered by RTGs.

You missed the point of the comment.

The point is you don't need huge complicated nuclear reactor to produce practically endless supply of energy in space, which is what the parent said he thought is a problem.

You probably need more energy than RTG but probably not as much as most people think. If you can apply a steady force for years, you would be able to give the required 10-100cm/s velocity delta to even large asteroid.

To what do you refer, that is not a "huge complicated nuclear reactor" but also is not an RTG?

There are and have been fission reactors in space already. RTGs seem to typically be in the hundreds of watts, while the reactors are more in the kilowatt range.

The reactors are not RTGs, and they are definitely a lot more complex.

Putting an asteroid into orbit would take an ass ton of fuel, more than is reasonably achievable. However crashing an asteroid into the moon or into Antarctica to mine would be much much easier.

> Putting an asteroid into orbit would take an ass ton of fuel, more than is reasonably achievable.

That's simply false.

First of all, asteroid is already on an orbit...

You can move stuff around solar system with relative ease and little energy if you are patient enough.

For this, you go very far from the Sun (ie. Kuiper Belt) where things fly very, very slowly and then you can use very little energy to nudge it in direction of Earth orbit. You can match velocities and use gravity assists so that the object is captured by Earth.

Technically you can use as little energy as you want depending on how far you are willing to go, how long you want to wait and how precise you can steer the object.

You take a nuclear reactor and you can use asteroid as reaction mass.

If you are still not convinced, these guys also don't agree with you: https://space.nss.org/technologies-for-asteroid-capture-into...

>It's a shame that the lunar gateway is useless

with the number of billionaires walking around, it probably can make a decent money as a tourist destination. Especially if there is an option to get down for a walk on the surface. Though it can become quickly at least partially outdated once one can just charter a Starship to make a quick long weekend trip around the Moon.

Oh great, the jet-setting class destroying the earth wasn't doing it fast enough: now the rich jerks are going to ruin the planet & burn gobs of energy going to into space.

What a dark evil Neuromancer 'the rich floating above the problems of earth (that they have created)' prospective.

You have just stated the plot for Elyssium .

Just to clarify, are you suggesting NASA should make a lunar gateway so billionaires can walk on the moon?

Otherwise taxpayers have to fully pay for the station.

Or maybe don't build the station. Also, the way the US government is funded, printing money is paying for things, not taxpayers.

Printing money is paid for by people who hold US currency. More money created means diminished value of existing money.

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