kerbiloid

A century later an adapted plastic-eating plankton will eat all oceanic plastic and begin to starve without tasty edible plastic bags. Adapted lobsters will lack polycarbonate for their crust. Rubberfishes will become less elastic. Adapted sharks will attack everybody in rubbersuit, ignoring naked swimmers. People will start an evironmental campaign "Save the ocean! Throw a bottle overboard!"

They would launch a pile of sticky tape and watch what sticks.

People are curiously watching the open fire torch near the greatest balloon of hydrogen around and guessing; how is it going.

Reading Dante's The Divine Comedy, you suddenly realize that all that pencraft prophecies were just up-to-the-minute pasquils pamphlets written to flint a night pot onto author's court rivals, but in artistic manner — and were not really intended to be prophecies. An author would be surprised a lot, if he knew what he did.

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If there were a tecnologically advanced civilization before modern human, we would have empty depleted quarries instead of rich mineral deposits, full of rusty gear wheels. So, people then would mine spots of high-concentrated rust instead of natural rocks untouched since early days of the Earth. Of course, no coal or oil, because they would burn them before us. "Only for research purposes, you see."

We should be very careful to keep the Earth rotation untouched. So, those who currently have 12h (probably America) would turn their... face in one direction, midnight (East Asia) - in the opposite direction, others - make their burn in radial (from/to the Sun) direction to compensate the angular impulse.

Turn prograde and perform an apoapsis burn.

Here is another thought experiment. What would happen if the entire XXI century Cuba suddenly transported back in time to XV century and replaced the XV century one? Probably, the Europe would be discovered by the Cuban fleet under the leadership of comrade Columbus.

Chameleons can into space too. They can all the same, and additionally they can throw their tongue, jumping from one part of the ship to another; catch things and MarkWatneys passing by in the space; manually tongually assist docking operations. Also, they are evolutionary more familiar for us and maybe are the space mounts (in terms of cavalry) of future.

Orion McOrionface.

We need giant flying comfortable saucer-shaped space cities (like in Visitors series) erasing any difference between space colony and ground settlement. Then everybody can easily choose what makes him/her happy. P.S. Mothership Zeta is fine too.

Hope, they didn't forget to extend their RemoteTech antenna.

(Turns out though, that's why the Sun looks so small this week...) Merry Aphelion!

As Minmus probably contains much ice (I can't imagine such slippery stones), maybe can still contains some ammonia under surface?

http://astro.unl.edu/animationsLinks.html http://astro.unl.edu/classaction/animations/renaissance/kepler.html

There's a lot of alumina on the Moon, but lunar carbon? OP's intention is to use local materials (especially alumina) as wide as possible. Well, the space history of the industrial sun concentrators is even shorter. At least, several dozens of small (several kW) reactors were successfully working on orbit in 1970-80s. Current Earth tech still doesn't mine ore on the Moon.

(FreeThinker told about Moon, but OK), then just vapourize the alumina with this energy - and you get more ISP than if making a chemical fuel from it for the same spent energy. Bring 10000 t of solar panels from Earth? Or melt 10000 t of alumina and silica to make solar panels, and anyway using nuclear reactor just to begin? Didn't understand. There are nukes, why to bottle solar power? Spacecrafts and rockets are made mostly of it.

Btw, that's a theme. That reusable booster can use ionized regolith dust. Again, not an aluminium chemical rocket.

OK, let's forget about graphite and so on, maybe they use some beam devices splitting the alumina. But 61 GJ/t won't disappear, it's an energy of chemical bounds — and alumina is one of the most tough substances in the Universe, planets are made of it. So, you would spend 11 km/s of energy to get aluminium fuel with 2 km/s of ISP? Probably you would better use railgun shooting with alumina balls.

IRL (from ru.wiki) a production of 1 tonne of raw aluminium requires 2 t of alumina, 65 kg of cryolite, 35 kg of aluminium fluoride, 600 kg of graphite electrodes and 61 GJ of energy. 600 kg of graphite is also not very usual thing on Moon, but 61 GJ / t = 11000 m/s if convert it to kinetic energy. Do you still want it?

Then we should select a proper place where ice, ammonia and stones are close to each other. Say, Joolpiter moons. And build on the Moon a ship to build a facility on, say, Ganymede, Then no problem with H,O,N,C,Al at all. Ideally, of course, near Titan. (Just when I planned something similar, I just defined for myself that the aim of space program is colonization of Laythe to build there a complex facility).

And as you need several times less industrial facilities, it's probably cheaper to import (several hundred tons?) of hydrazine or hydrogen for your nukes. Once the ship is assembled, you can attach the booster as its low thrust propulsion module.

Once it's already build and equipped, I should prefer reusable nuke booster to lift its large parts.

I doubt a little that building a ship in L1 is easier than on Moon. Of course, zero-G instead of low-G, but no stable place, problems with waste, waste heat, storage and so on. On Moon you can place reactors behind a mountain. at least.