I used to work on near Earth satellites that had a <15 minute contact window about 10 times per day. Sensor requests and aiming commands would get pre planned about 2 days out with a gui that would let you point and click and it would package the proper commands automatically. Usually a team of ~2 analysts would work together to make sure all of the requests would make it into the upload package but always with a gui.
We could also get a short notice request for data and could speed through the process in about 2 hours. Still just with a gui. The manual commands would never get sent ftp style because we only had short windows of contact because the dishes on Earth would only have the craft in the sky above them for so long.
Some satellites pay for time on a set of air Force satellites in Geo called TDRSS to give them continuous comms but those are really expensive and really slow compared to what you can downlink to the ground.
Wow, I looked at it and was just about to come back here and bash non-functional science fiction design, but it's actually completely usable and every element is displaying relevant data.
Cool looking, but I hope the real capsule's UI looks absolutely nothing like that, judging from the stories I've heard of the Model 3's touchscreen locking up and needing to reboot mid-drive fairly frequently. Not everything ought to be a touchscreen.
Space resource usage could first happen with asteroids, not on the Moon or Mars. Propellants mined from asteroids can be transferred anywhere with very low delta V and low thrust. It just takes time.
The moon would be acceptable and Mars is simply the next big thing.
Esp. the moon because you can use a cannon to launch spacecraft so you don't need to use fuel on it (if you'd do it with a magnetic cannon you could do it entirely with solar arrays).
Escape velocity is more than 2km/s, roughly the speed of bullet, that's a bit too much to "launch spacecraft" or am I missing something?
ps. it's actually interesting concept, you could have something similar to medieval catapult on the Moon and throw rocks on Earth which would be equivalent to nuclear explosions, no?
Accelerating from 0 to 2km/s at 3g (suitable for humans) takes about 60 seconds, and a barrel that's about 70km long (40 miles). That's no easy feat, but certainly achievable. You can get around the barrel length by building a circular barrel (with it's own set of problems).
Just launching cargo is a lot easier, we already know how to accelerate things to the speed of a bullet in a variety of ways. Scaling up a railgun to handle heavier bullets is comparatively easy.
A single long metal rail would suffice, with a maglev acceleration system. Lack of atmosphere makes it easier too. Could probably manage up to 10g with a bit of scaling at the ends, although might be bad for people who'd been on the moon for a while.
For non-alive payloads you can accelerate at >10g and get a comfortably short rail to fire the bullet from.
For alive payloads, the rail becomes longer.
The advantage is that on the moon the low gravity and no atmosphere make megastructures like this easier to build. Energy is also no concern either, you have pure unfiltered sunlight for about 15 days each month on each side of the moon.
It sounds cool sure, but what resources do we even want from asteroids? We have plenty rocks and ice on earth and even something like iron ore is just 0,08$ per kilo. Getting that kilo to LEO is 2200$ and getting cheaper every year. We have all the resources and infrastructure we need right here on earth while absolutely no one has any idea how to manufacture things in space.
A lot of heavy rare earth metals can only be found in very limited concentrations in the earth's crust, with the largest concentrations all being from asteroid impacts. As a consequence, these metals are incredibly valuable. A single high-concentration asteroid, could provide more of these metals than has been mined in the history of the earth, in high concentrations, and may be able to make a host of applications economically viable, which previously weren't.
Yeah, heavy REMs are still expensive but there is really no reason to believe that they'll stay that way. New sites will be found, new extraction techniques will be tried and new processes developed and then the problem will go away. Sure, it could happen in space but it's so much easier to do here on earth that it might never be worth it to go to space for it.
Yes, but if several thousand tons of iridium, platinum, or various rare-earth metals could be captured & towed to Earth orbit, the payoff could be astronomical.
Suddenly there would be so much of a supply that the sale won't be profitable any longer. That's probably the reason why no one is extracting rhodium from nuclear waste, where it is a common fission product.
I've been told that the trucking industry needs every year more platinum than has been mined in all of history. Since there obviously isn't supply they instead use alternative means to achieve their emissions goals.
I'm not an emissions system engineer so I can't evaluate the truth of the statement. If it is true, and supply existed: it would create demand, potentially it could even drive up price as potential users quit using less desirable alternatives.
The demand is mostly in chemical industry and very inelastic. No one is going to put another plant on line because platinum group metals are cheap (but plants may be pulled off line because the economy is in the dumps, as happened in 2008 and 2017). Even small increases in supply will lead to great drops in price. You can only hope that a plentiful supply would encourage new uses.
At first it is not about metals, but water. Water is the oil of space. You can use it to make propellant, human/plant consumables, radiation shielding, and for further chemical processing. Once you have cheap water in cis-lunar space, it becomes 'easy' to move payloads around the Solar System and start the process for other resource utilization.
> absolutely no one has any idea how to manufacture things in space.
That's a bit of an overstatement. We have a 3d printer on the ISS and me make great strides in producing fiber optics in space that are superior to what we can do on earth at similar price points [1].
Fuel is the big one. A fully-loaded Space Shuttle is about 2 million kilograms; getting one to orbit and then refuelling it up there would cost several billion by your metric. This requires either finding watery asteroids or comets, or experimenting with metal-oxygen rocketry systems.
There's the advantage of not having to mine _the Earth's ecossystem_ for resources, which is what we've been doing so far, impacting the environment.
Mining a rock which has been drifting to space is basically getting an eco-friendly resource stream.
Once you have capabilities to build in space, going down gravity wells makes zero sense.
Want to build a factory or physics lab in space. You just mine things there and build them there. After a while you are looking at permanent colonies and then it's useful there.
Iron is the most abundant element on Earth. The likes of platinum or gold are significantly more expensive (and not just because of scarcity: they have useful electrical/thermal/mechanical properties).
No, it's not. I'm pretty sure it's silicon. Iron is relatively rare (but not as rare as platinum or gold of course).
Iron is the most abundant element in the Earth, but not on it. The core is full of iron. But that doesn't help us at all, because we can't get to that. We can only access materials in the crust, and there isn't much iron there.
It says "in the Earth's crust". That indicates to me that the biosphere and the oceans are not being counted. Also, it's giving abundances by mass, which is not the only way to do it (I was actually thinking of abundance by atom count).
Later in the same Wikipedia article, the top eleven abundances by mass for the ocean are given: oxygen and hydrogen are the first two, carbon is #10, and silicon doesn't even make the list.
No figures are given in that article for the biosphere; my statement of carbon being the most abundant for that is based on the fact that it forms the "backbone" of all of the main types of molecules in living organisms: proteins, carbohydrates, lipids, and nucleic acids.
Carbon may be the "backbone" of organic matter, but that doesn't equate to the Earth's crust having a lot of it. Iron is the "backbone" of our red blood cells, but that doesn't mean we actually have that much iron (by mass) in our bodies or even our blood.
As for the "crust", the definition of the Earth's crust I'm pretty sure includes the oceans, the seafloor, and everything down to the mantle, so the biosphere and oceans should be counted there. Hydrogen doesn't rank highly because it has little mass compared to other elements. Atom count seems like a pretty pointless metric; we're talking about resources available for mining, in which case mass is what counts.
Of course silicon doesn't make the list for oceans because it's mostly water, and a lot of dissolved CO2. Count the seafloor and you'll find lots of silicon (and probably some iron, aluminum, titanium, etc.).
> the definition of the Earth's crust I'm pretty sure includes the oceans, the seafloor, and everything down to the mantle
If the crust included the oceans, there wouldn't be different figures for the oceans in the same article.
You make a valid point about the seafloor being part of the crust; but I didn't intend to include the seafloor in "oceans".
> Atom count seems like a pretty pointless metric; we're talking about resources available for mining, in which case mass is what counts.
That depends on what we're mining the resource for. For example, if we're mining for metals to use in catalytic converters for vehicles, atom count is the relevant metric, since the catalytic effectiveness depends on the number of atoms, not on the total mass.
No, it isn't; each hemoglobin molecule has just four iron atoms in it (IIRC--each heme structure has one, and I think there are four heme structures in one hemoglobin molecule). Most of each such molecule, by either mass or atom count, is carbon. And each red blood cell is more than just hemoglobin molecules.
One of the plot points in Neal Stephenson's Seveneves [minor spoiler alert] is an Elon Musk-type character that melts a nuclear reactor into an ice comet to make a thruster that uses the comet as fuel. I always thought that was really neat.
Don't forget Asimov's The Martian Way. First published in November 1952 (!!!), the story is about how Earth refuses to export its water to Martian colonies who are using them as reaction mass on their spaceships. The Martians, in response, fly to Saturn's ice rings and ship a huge chunk back by using it itself for reaction mass.
I loved his "Robots"-trilogy (actually I think that there was a 4th book but when I the first 3 again recently I haven't been able to find the 4th one as ebook on Amazon & Kobo :( ) => they definitely motivated me to learn & program my first backpropagation network :)
Kind of similar characters & practical approaches used many times in John Ringo's "Looking Glass" and "Troy rising" sci-fi series:
story & characters are definitely "american-style" (very direct & aggressive), but in these cases I ended up liking quite a lot this approach (basically it fits the setup of the stories because of the fight for survival of the species).
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List of books (Spoiler alert - don't read the plots):
I would be really neat if we could get a demo mission that converts some local resource on an asteroid to fuel and refuels an orbiter. Perhaps electrolyse some ice to Hydrogen and Oxygen.
What in particular makes “factories in orbit” seem implausible? We’ve already got/had a limited one of those in the form of the 3D printer on the space station.
Sure, fully automated mining, refining, QA, etc. isn’t ready yet, but it’s not implausible, and those things are all still increasingly automated even down here on Earth.
That's right. Iteration is key. Start small here on Earth, then build a somewhat crude factory in space. Solve any unexpected challenges that may arise, rinse, and repeat. Eventually you'll have factory-producing factories.
Likely, the early stages of the solar economy will resemble the Atlantic Slave Trade of the 16-19th centuries[0]. In the horrific middle passage, slaves were'sourced' from Africa and sent to the Caribbean for work on the plantations. Then the cash crops of cotton, sugar, tobacco, etc were sent to the manufacturing centers of North America/Europe. These manufacturing centers then sent finished goods like guns and ammo back to the colonies. Sir John Hawkins, a pioneer of British slaving, was the first to run that route, making a profit at every stop[1].
Similarly, we can expect that the early solar economy will provide opportunities for the same, though there is a lot of still undiscovered issues at hand.
Here, Mars/Moon will make the food and other 'simple' goods that are then sent to the Asteroid Belt. This is because the delta-V to get foodstuffs and goods off Mars/Moon is a lot less than on Earth and, depending on more surveying, there seems to be a fair bit of water on Mars that you can use. It seems thus far that corn-pone and beef-steaks do not grow well in 0G, though that remains to be seen.
These simple goods and food-stuffs will then be consumed by the Asteroid Belt in the use of mining for rare-earth elements and in production of vehicles and fuel for use in the outer solar system. The mined elements and materials will then be sent back to Earth for use in highly complex machines and other things.
Highly complicated machines built by people that do not want to raise their kids in the Belt or on Mars/Moon will then be sent to Mars/Moon for use in production of simpler goods.
A company with skills in (robotic?) space shipping and landing could make a profit at every gravity well.
This triangular trade is not likely to last very long as greenhouses are set-up (if possible) in the belt, manufacturing and leisure are made easier on Mars/Moon, and as techniques and science are improved on Earth.
Most likely in the Moon first. It would be relatively easy (compared to alternatives) to send small crews for six months shifts. The facilities would be underground to avoid radiation and micrometeorites hits.
For really far bases you would need spin gravity in a hollow asteroid for the staff.
How so? Can't you do it from the Moon with low delta v as well? (honest question) And I think the Moon's proximity and "static" position relative to the Earth is another great advantage.
The question is not only escape velocity, if you want to fly away from the Moon, you still need to escape Earth and the Sun. The other part of the problem on Earth is atmosphere with its drag and the fact that some kind of propulsion, like ionic, is impossible.
Edit: hmmm... it seems that escaping Earth and the Sun would be easier from the Moon, since the Moon trajectory components include already the 9 km/s and 30 km/s of Moon and Earth's orbits. Once in Moon's orbit, with the right angle and a little push, you should be able to escape Sun.
There are simply more players on the field now. With ESA, JAXA, CNSA, among others, and the emerging private sector we can diversify into many exciting space projects instead of going for a single (no matter how amazing) moonshot.
(Self promotion warning!) If you find space science, CubeSat engineering, and space startup news interesting, I'm starting a short weekly email newsletter that I think you will enjoy. https://goo.gl/forms/uGi2AL7ELpJK86bx2
In the case of commercialization, should we worried about a failure-to-launch scenario? We supposedly only have enough fuel to get a volume of about Mount Everest into space. Given the economics of climate change being so fucked up and a tragedy of the commons, could we doom our species to spending the rest of eternity on this decaying rock if we allow market forces to shit away all the fuel required to make us interplanetary?
As others have mentioned, the propellant for three major upcoming rockets (Blue Origin's New Glenn, ULA's Vulcan, and SpaceX's Starship/Super Heavy) is methane (plus liquid oxygen).
Currently that methane is coming from natural gas, and represents a tiny, tiny fraction of our current natural gas use. If we didn't want to use natural gas, methane can be made from hydrogen and carbon dioxide. This is critical to SpaceX's Mars plan, as they're planning on making their propellant for the return trip once they get there. If you can produce it on Mars, you can definitely produce it on Earth.
I’m not convinced we do have a limited earth fuel budget as you say. There’s lots of options for rocket fuel and many of them are highly abundant or can be synthesised.
For example, hydrogen and oxygen are the 1st and 3rd most abundant elements in the universe, so liquid oxygen and liquid hydrogen fuel is always going to be an option
We have lots and lots and lots of fuel, in part because rocket fuels are varied. Many of them can also be synthesized through the use of water, atmospheric gasses, and power.
For example, Blue Origin and SpaceX are developing launchers that run on methane - fantastically plentiful on Earth in the form of natural gas. Delta IV runs on hydrogen, which can be synthesized through gasification or electrolysis. Falcon 9 and Atlas V burn kerosene, also very common.
The real issue is whether, at high launch rates, this will become a meaningful contributor to climate change; hopefully through use of space-based resources we can reduce the up-mass requirements enough to avoid that problem.
ULA's replacement for the Delta IV and Atlas V, "Vulcan" uses the same BE-4 engine as Blue Origin's New Glenn, so it will be methalox as well.
It's a slightly more complicated platform (using hydrolox for the upper stage, and optional strap-on solids for the booster), but the bulk of the propellant is methalox.
Late to the party but... we don't need fossil fuels to launch rockets.
Aside from synthetic fuels, you can launch rockets on methane. Can't make methane? (You are a robot society by now, because it would mean there is no biosphere anymore). Still fine! We can convert our oceans into fuel (hydrogen + oxygen), given energy input. Energy can come from renewables, nuclear, etc.
No, we are not going to run out of fuel for as long as we have water.
Considering SpaceX's Raptor engine currently in development is going to use methane as a fuel source (produced by cow farts and rotting garbage among other things), I don't think this particular issue is something to place at the top of your worries about global warming.
I'd be more worried about conflicts breaking out due to mass migration due to parts of the world becoming harder and harder to eek out an exsistance in.
Depending on what GP meant by "decaying", I can see two answers.
If they meant decaying in the "climate change is destroying the world" sense, then presumably the idea is that we've learned our lesson and won't destroy the next rock the way we have this one. Debatable, but at least the next rock is unlikely to have dead dinosaurs for use to dig up and burn.
If they meant decaying as in "the sun is eventually going to swallow us up", the presumably we will spread humanity across a bunch of decaying rocks, and continually migrate for the most decayed to newly formed rocks.
When getting stuff into space it's mass that matters, not volume. Even if you mean mass, that's equivalent to the mass of 39 years worth of all the world's cement production combined. Which is a fair bit. Plus rocket fuels are manufacturable from renewable resources.
Partly for that reason (but mainly for the cost) the future of space access isn’t rockets, it’s things like orbital rings, launch loops, active support towers, momentum exchange tethers, etc.
We don’t have them yet because they are expensive investments. It’s like flying NYC-SFO because building a 747 is cheaper than building the I-80 freeway — It seems like a no-brainer now we have Silicon Valley in one and Wall Street in the other, but imagine it from the point of view of Teddy Roosevelt rather than Franklin Roosevelt
There has never been a single instance of when a resource became actually depleted with no substitute. None in all of history. It's however a potent scare story used by communists to advocate communism which always has failed to produce most things in sufficient quantities.
Why does space advancements made by non-US agencies only receive after-the-fact notice in the US media? I would like to know about these before, and in much more detail!
Couldn't find this in the article: How is it expected to reach the Earth in 2020 when it took 3.5 years to get to the asteroid? Will it begin its return when the asteroid is closer to the Earth?
The craft uses ion engines for propulsion. Extremely efficient but also extremely week. As a result it took a long time for the craft to match it's orbit. Had it not done this it would have either flown by or smashed into the asteroid at extraordinary speed.
To return samples to Earth it does not need to match it's orbit since the atmosphere provides a convenient way to slow the samples without powerful engines and large amounts of fuel.
I couldn't either, but on the Wikipedia page[1] for Hayabusa-2, there is a gif of the flight path. Maybe it took 3.5 years to achieve proper alignment/speed to land on the asteroid, but due to the larger size of earth and the position of Hayabusa-2 when it begins its return, it will be much more straightforward?
Getting into an orbit next to some other small object is kind of hard. In the GIF you can see Hayabusa-2 making multiple orbits below the asteroid's orbit to catch up (lower orbits are faster) before it raises its orbit to the height of the asteroid. Once it reached the asteroid it had to do another correction to the orbit to make sure they stay together.
In comparison, meeting something massive like a planet is very single: go into any orbit that nearly hits the planet, and when you are there slow down enough to let charit gravity pull you into an orbit around that planet.
tl;dr: more gravity makes rondevous easier and quicker
>>Due to its high density, shaped charge and explosively formed penetrator liners have been constructed from tantalum. Tantalum greatly increases the armor penetration capabilities of a shaped charge due to its high density and high melting point.
Have you read of Akatsuki, JAXA's Venus orbiter? It suffered a grievous propulsion failure in 2010 when a pressurant valve failed, causing its large main engine to run oxidizer-rich -- its nozzle thus shattered and fell off. It was therefore unable to enter Venus orbit in 2010.
However, JAXA engineers saved the spacecraft and salvaged the mission: after five years of orbiting the sun (beyond its expected lifetime), Akatsuki's far smaller attitude-control thrusters were lit up (for 20 minutes straight!), causing it to successfully enter Venusian orbit in 2015, and it's been functioning ever since.
On 9 May 2003, Hayabusa (meaning, Peregrine falcon), was launched from an M-V rocket. The goal of the mission was to collect samples from a small near-Earth asteroid named 25143 Itokawa. The craft rendezvoused with the asteroid in September 2005. It was confirmed that the spacecraft successfully landed on the asteroid in November 2005, after some initial confusion regarding the incoming data. Hayabusa returned to Earth with samples from the asteroid on 13 June 2010.
It's inappropriate and beneath HN standards to classify an entire country as being typically ignorant. Such a wild, broad generalization about hundreds of millions of people is impossible to support.
It's not a generalization about hundreds of millions of people, it's a generalization about the public education system in the US, and it's entirely valid. The US consistently ranks at the very bottom of public education rankings of all industrialized nations. This isn't inappropriate, this is supported by reams of research and explains how people in this thread can be ignorant about worldly matters.
> It's just typical American ignorance about anything outside of America
That's a generalization about hundreds of millions of people. You were very clear.
When it comes to education, according to the PISA, at a 15 year old level of development, the US ranks just behind Norway and ahead of France, Sweden and Austria on science; ahead of Israel and Greece on mathematics and just behind Slovakia; ahead of Spain, Austria and Switzerland on reading and just behind the UK, France, Sweden and Denmark.
On reading the US is one point behind the UK, and two points behind France; the UK is 37 points behind Singapore (the top) for comparison of the scale.
The US is 20 points behind the UK in mathematics; the UK is 72 points behind Singapore and 29 points behind Switzerland.
The intended audience is mostly China ("look at how similiar to an ICBM this space rocket is"), but the program is scientifically very useful despite that.
Due to the time it takes to prepare and launch one, liquid fueled rockets have very limited strategic or tactical relevance... The US learned this with the first generation of titan ICBMs which were stored horizontally and intended to be erected+fueled on demand for launch.
Russia/the Soviet Union built the world's first ICBM [1] and has arguably the most acomplished space program in the world:
They were the first to launch a satellite, the first to put animals in orbit and the first to retrieve animals savely from orbit, first EVA, the first probe on the Moon, on Venus and on Mars, the first robotic rover, the first woman in space as well as the first hispanic and black person in space, the first space station as well as the first permamently settled one, ...
I don't think their capabilities tell us much about Japan's.
The US doesn't buy rockets from Russia, ULA uses the RD-180 engine until the new Blue Origin engine is ready. The ULA rockets are eg Atlas V (uses the RS-180) and Delta IV. The Delta IV rocket and heavy lift variation uses the RS-68 [1] engine, which is US tech. Their new Vulcan rocket will use the Blue Origin engine.
SpaceX is certified for critical / national security launches and does not use Russia tech.
ICBMs stand for InterContinental ballistic missile. Intercontinental being the key word. Last I checked both china and japan were on the same continent.
I work at NASA. Trust me, it's common and sad. Barely anyone here knows the existence of this amazing feat of human engineering. I guarantee if the U.S. was involved in any way, it would be everywhere.
Chances are that a highly developed alien race won't be as bloodthirsty and barbaric as the human race, so "weapon" might not be their first thought.
If you're space faring on a large scale you probably had to leave conflict and infighting to lesser races, just so you could focus energies on making that leap.
What are you talking about? Infighting among humans has always been one of the main drivers of innovation. Do you know who invested rockets, and why? The Germans did during WW2.
> That's just another argument that humans are truly a race of barbarians.
relative to what? we don't know how violent alien species are. they could be very peaceful in comparison, but it is just as likely that they are more violent than we are.
You think that evolution on another planet isn't going to put the most efficient killer species at the top of the ladder?
All the evidence available to us (Earth) suggests that the best killer on the planet will be the dominant species. It's been that way for billions of years.
If the Remembrance of Earth's Past trilogy taught me anything, it's that keeping a low profile is the safest choice :) Highly recommended if you are into sci-fi.
I think all of the points that the video makes are more or less addressed in the books. Don't want to spoil too much, but and important part of the argument _for_ complete genocide of everybody you meet is that (the book argues) any other more primitive civilization can, at any moment, go through a sudden technological explosion and leapfrog yours. It's imperative to eliminate them. The whole reasoning is based on the assumption that this can happen (not saying that it's a realistic assumption). The video doesn't mention this at all, and most of its arguments are rebutted by this assumption.
The Dark Forest idea is based on those axioms, so if you believe the axioms hold in our universe then the book conclusion holds.
The video argues many points, an important one are
1 you can't stay hidden, advanced civilizations will detect you or can send probes to destroy any viable solar system,
2 if you try to kill everyone else you will eventually find someone bigger then you so maybe the strategy to make alliances is better, you will have a better chance surviving in an alliance when you eventually meet something bigger then you.
It's an 18 minute video. Does it include the point that Earth has been broadcasting "I've got life on me!" for about a billion years now, ever since the Great Oxygenation Event?
Since I realized that, I've stopped whatever slight worry I may have had about the "kill everyone you discover" theory. If it was going to happen, it wouldn't happen in the near future because some of our radio waves finally got somewhere, it would happen eight or nine hundred million years ago and we wouldn't be having this conversation at all.
The reason I suggest the video is to help people that feel "depressed" or similar feeling after finishing the book, the book had this effect on me and I seen people on reddit having similar feelings after finishing it. So my intention is to help , I don't want to discredit a book or theory or promote something. (I loved the books)
