kerbiloid

That's an idea. Cat photos.

Only while humanity grows, while the industry can't recycle any slag to a combination of useful simple substances (just because a slag is usually a stable substance in an "energy well"), while you need to produce much more than you consume and can't recycle the excessive goods back. If you have a 99% recycling, and there is more or less constant amount of people, your need in new resources falls down to a ridiculous level and can be easily covered with the terrestrial ones, with no need in asteroids. So, only the most rare metals will be the aim of any extraterrestrial industry ever.

I'm sure, it is. But dry facts are: the payload of Atlas V is successfully delivered (and that's almost fail), yet none of the rocket stages have been reused again (and that's almost success). That's what I call: SpaceX glass is always half full, any another one - half empty.

A video message where Angelina Jolie reads something like: "Hi, dear extraterrestrials! We know that you are receiving all our TV broadcasts and speak our languages, so let's have a talk,"

And the only thing understood by the ET astronomers was: "Look, this is a transmission of reasonable beings. They play tetris!"

If this is indeed an alien megastructure, we'll have enough bricks. But let's hope this just a giant space moth somewhere between us and KIC 8462852, from time to time flapping with its wings.

Steel is Fe mixed with exact and predictable small amounts of C and sometimes Ni, V, Mn, Mo, W, etc, created from a wild mix of iron oxides polluted with sulfides, sulfates, etc. No need to store it as a pure Fe, it's impractical. But btw if you, say, heat a piece of ore to 10000 K and then magnetically separate ions, you would have no choice rather than to get pure elements into different pots and then combine them in required proportions. But as I've told above, "to atoms" here had been meant just like an idiom. If your goal is another, in the end you exactly have the same amount of nickle, silicon and other excessive elements as a large slagheap near yours, but as a mix of chemicals. From another side, any stone is a combination of Al,Si,Mg,O,Fe,etc. All of them are required on Earth, and the Earth contains many different stones. So, splitting a stone to its elements on Earth, probably you would discard only oxygen (as there's enough of it), sulfur (as its the most annoying impurity, and there is much of it) and, say, calcium, just because. I.e. you again would have nice gypsum to mix it into concrete.

I've used such splitter just as a sample of a minimum ISRU refinery opposite to a full metallurgical or chemical facility, with dozens of columns, reactors, basins, adsorbers, adsorbent regenerators, etc. Just as an ultimate magic caldron. Of course, there is no need to split everything such deeply. I mean, even if create a tiny processor of matter available for space pioneers, anyway the Earth provides it with much more resource base. P.S. What you've described about the metal processing is true, but as you can see, the main product of any metallurgical plant is a pure element (steel slabs, aluminium slabs, copper ingots, etc.). Just some of them a better to store like a simple composite chemical substance, but also as a single simple substance. And all this process is nothing more than extracting of its pollutions.

It needs to be cooled anyway. At least because you don't like the liquid methane temperature in your cabin. Except of cryotanks, other parts of ship are warm. (Yes, -100°C is warm compared with liquid O2 or CH4). Heat flows through the ship construction. Some (small) part of liquid gas gets warm and vapourizes. Vapour amount grows, its pressure grows. You must either actively cool the tank making the vapour again become a liquid, or drain into space a small excess amount of vapour through a vent valve. You can shade it from sun, you can stir it to cool the warm piece with cold pieces, but this is unavoidable. The more volatile is gas - the more frequently you exhaust this excess. Hydrogen is beyond comparison, of course, but any another liquified gas also does this. Hypergolics are not so volatile and due to this they can be stored for years.

It's much easier to force a resource recycling on the Earth than to mine and deliver resources from other planets (even if they really are there). Every aspect of industry requires at once enormous amounts of facilities, storages and substances ready to use. On the Earth they were being evolutionarily built for centuries. On another celestial body you need either to build a huge metallurgic facility at once (which means you need to mine and produce the mineral in really huge amounts), or just to send a raw ore to the Earth where a metallurgical corporation already has the required plant. The second way is much easier. Also, say, a platinum corporation, sponsoring the mining project, needs ore for their plant, not an extraterrestrial colony itself. Almost all elements you can mine outside the Earth are so common here, that it has no purpose to dig iron or potassium on the Moon. Probably even titanium. So, only very rare elements mining would find a sponsor. OK, say, now here appears a portative "smelter" which can split any piece of matter into atoms and store them separatedly. Nothing too fantastic in such presumption. Now you don't need all that metallurgical plants. You extract a rock, split it into atoms, then you print goods with 3d-printer. So, all you need is to deliver this mega-smelter with mega-reactor and mega-printer to any asteroid or planet which you prefer, and to start mining/splitting/printing. But on the Earth there is already many times more of "empty rock", "solid waste", "useless stuff" to be recycled. And this "smelter" is the greatest way to utilize any useless trash, getting pure elements and printing the new useless trash. At some moment there is no need to dig new portions of ore at all. Today a person eats sandwiches, discards empty sandwich paper, old boots, visits toilet. Trash and waste water are being delivered to the recycling facilities. Tomorrow he/she gets a new paper with sandwiches, new boots - made of somebody's yesterday atoms, just shuffled. Now all terranean metallurgical and chemical industry turns into a "environment-friendly" recycling lego. So, 1) Still nobody needs those extraterrestrial elements as all of them are already here; 2) Still only very rare elements are indeed required, and maybe really mined on asteroids. And as probably there are not many places in Solar System were cesium and holmiun are laying as ingots, not many extraterrestrial mines would be. So, now the only purpose to colonize at least something is a vault creation. But now it's even more pointless than before, because now you can build all-recycling self-sufficient closed-cycle underground cities on the Earth. This will overcome almost any disaster which can make the Earth even worse than Mars, except the planet destruction. But if burst the Earth, any Mars colony will anyway be eliminated by falling pieces. So, the Earth will stay the only planet colonized humanity. Scientific and observational outposts, rare element mines. Not real colonies.

The electicity kills much more people every year than the radiation ever.

I mean, reusable boosters. Landers, NASA's Morpheus , reusable Gemini and TKS re-entry modules are another thing.

I'm afraid, the stage landing experiments were lasting since early 60s, yet with the same luck: yet none of them flied again. (Except of Shuttle components of course, but that's another story.)

Of course, they can exist.An ultimate question: how long. Biological evolution needs a billion terranean years,

A glass is half full or half empty depending on is it SpaceX glass or not. 6 seconds less worked the 1st stage, 60 seconds more worked the 2nd stage, the payload is successfully inserted into its orbit. Almost fail. One of six (or how many) stage landings finished successfully (and nobody knows whether that stage can be repaired), the next one crashed the barge. Almost success.

Yes, I see,But what if its dispersed microwave radiation occasionally hits a, say, TV parabolic antenna and it gets back a reflected and concentrated beam?

Does the brander count?

What if it hits a parabolic antenna opposite to it?

Oort cloud still exists (if exists). Orbital speed is ~=50..100 m/s there, and orbital period ~= 100 mln years, i.e. less than 50 turns since the Solar System had appeared. So, "early" time there lasts for 108..109 years.

So, the hypothetical Planet 9 is accused in dwarf planets kidnapping. And it's (if 's) presumably just several Earth masses heavy and 1000 AU far. Sun is 300000 Earth masses. So, a companion star, say 100000 Earth masses, orbiting 100 times farther than the hypothetical Plan.9, i.e. in 10000 AU from here, would: 1) kidnap outer dwarf planets, making their orbits unstable; 2) stir the Oort cloud as a skimmer, periodically throwing the comets in all directions, also towards us. Dinosaurs would have no chances.

"Pocketbook of Young Scout", 2250 A.D. edition. "100 ways to grow and cook potatoes in vacuum." "Physics for Elementary Schools, Vol. I"

Probably somebody occasionally dragged the maneuver node with mouse.

And from?

Naturlich. Don't we speak about a space yacht 100 years later?

No more planets until the Minoan script A and Phaistos Disc are decyphered!