kerbiloid

We can start small. This but in orbit. 50 years later people will say thanks for it. A nuclear-powered orbital scavenger should gather the upper stages and move them to the orbital scrapyard. (Btw, the same theme with interplanetay ships fueling. Instead of taxiing huge tanks up and down inside a shuttle, make them single-use and collect in the same way.)

If possible, connect your notebook to an external display and watch again.

Space and spaghetti - what can go wrong? Here you go. Something medieval, please.

Also when something goes wrong in ISS or Mir, they just send supplies (sometimes - a repair team) and fix it. If something happens with a cycler - you can do this only in the same short periods when you send the Martian ship. So, either they should work fast and return before the cycler gets too far from the Earth, or the Martian expedition should be repairing the cycler themselves (though, a nice way to make their journey not so dull), or you have to have all cycler systems redundant, so in fact build two-three cyclers in one, but use only one (a ship lifespan is only two years, while cycler should float for decades without major repairing and with no fast escape option). *** Also what if by some reason (ballistic, technical) the ferry ship docking failed? The ferry ship misses, it unlikely can return to the Earth due to delta-V requirements. So, it should perform a Martian flyby and 1.5 years later return to home (like Apollo-13). To keep the crew alive it anyway needs protection and supplies for a full Martian trip. (Also this means that simple Hohmann trajectories are risky: their orbital period doesn't match the Earth year. If possible, better use something like 2-year orbit, exactly matching the Earth orbital movement. Yes, this needs more delta-V, but you can get inspired by Apollo-13.) So, if a ship anyway requires a full-scale life support (and anti-rad protection), why bother with extraplanetary rendezvous and docking? The only reason - artificial gravity. If they fly there under normal gravity, they don't spend their health, get to Mars healthy and you can pay them less.

Solar wind is just one of deadly radiations. Galactic high-energy gamma-rays are omnidirectional. 6 m of reinforced heavy concrete (with boron and lead admixtures) around a nuclear reactor active zone is enough to protect personnel around it. 1-2 m of ground over a vault protects from nuclear explosion fallout. As estimated doze for Martian expedition is about several Sieverts (much less than in both mentioned cases), you don't have to move a whole asteroid to feel safe. About a meter thick protective layer looks enough. So, instead of redirecting an asteroid, it's much easier to bring several hundred tons of boron-lead mixture and pour it in hollows around the orbital station habitat.

We should also take into account possible lifespan of an orbital station (tens of years) and frequency of its orbital turns. According to the first link, at least 2 years per cycle. This means, a cycler can support just 10-20 interplanetary flights before it becomes too old to use. Then Mir/ISS/Skylab-type cycler will be just dangerous to visit. While a huge, thick, and spinning wheel-shaped station will be a museum of outdated technologies (and probably also worn). So, for me a (heavy, thick, spinning) cycler makes sense if you are going to perform an agressive 20-years lasting assault to Mars. It doesn't make sense if you are going to send ships from time to time or if you are going to use it longer. Also, to build such heavy station in heliocentric orbit you need high-ISP ships to deliver its components. This means that when the cycler creation will be completed, very likely your current ships will get to Mars directly in weeks. P.S. Of course a cycler unlikely makes any sense for anything beyond Mars (due to enormous flight durations). So it is by definition a technological dead end.

It requires: At least 2 extraplanetary rendezvous per flight. Up to several weeks long taxi flight duration (twice: near the Earth and near the Mars). So, a full-featured life support in the ferry boat, not just snacks and diapers. Additional fuel (and longer taxi flight) because Earth and Mars orbits are not coplanar, so the ferry boat should undock and turn its orbit plane before the cycler reaches a planet. Same amount of supplies (as mentioned above) and fuel to send them to Mars through the cycler. From my amateurish pov, this scheme makes sense only if the cycler is a monumental-looking space station with artificial gravity and meter-thick protection layer around the habitat. Then of course, they don't have to launch these several thousand tonnes again and again. Just several hundred tonnes of a ferry spaceship. Unlikely an asteroid, as: 1) why need one, when all required goodies can be placed in a station built on a desired orbit; 2) is a heap of frozen stones (so-called "asteroids") enough stable to be sure that it will not deform and bury the hotel.

If I don't miss something, when such thing orbits around the Earth, they call it "space station". Just it orbits around the Sun.

Happily, the person, whose body I am possessing in that reality, is dressed in a cop uniform of the police department from another city district. So, my avatar shoots a bank manager and puts the bag with money into his hands, taking several stacks and putting them into the uniform pockets. When the cops arrive, my avatar explains them that the manager was attempting to rob the bank and capture hostages, so my avatar had to stop him. Then my avatar gets out from the bank to make a call and escapes... I wake up. Scenario: Dark, moonless night. Time, when a human is so weak, so vulnerable. A dark house looking very familiar to you. Your house. No light, no sound. You are carefully crawling into the window trying not to wake up what sleeps inside. You make one step... Another one... Two steps more and you are in the kitchen.... Carefully you take off your secular garment and put in on a hook. Now you are inside, time to get potions from the hide and use them. You extend your right hand and pull a lever... Loud squeak of the rusty door hinges make your whole body to numb! You are counting you heart beats... Nothing... Looks like you just had rolled a successful saving throw. But you can see that a soft, calming light comes to life from inside. You take a strange semi-transparent jug with a sticky white substance inside and stir it three times. Counterclockwise, as usual. You hold your breath and make two big drinks and one small. Nothing happens. Now you take a little pack of greenish pastilles. They smell like mint, but you don't know exactly, what are they made of, and you don't want to study this secret. You have enough your own ones. So, you just clean your lips with the back of your hand, close your eyes and put a pastille into your mouth... Wait... Oh no... A shrill beeping pierces the night! Once, again, then once again... You desperately slam the fridge door trying to stop the "door is open" alarm. How could you forget to do this a little earlier?! But once the door gets closed, the darkness falls again. And in the darkness you trip over a stool under the table. You hear a voice... Sweet as honey, but carving as a razor... - Darling! How can you explain that you are returning to home at two o'clock in the morning? You drop the plastic jug with remains of yogurt and swallow the mint gum. A question is already made.

It's even better.

Because roots are carrots. When you get from sqrt(-1) an imaginary carrot, can you feed it to a real parrot? A nerdish way to say "Anything you want!"

(Not a question, but unlikely merits its own thread. ) Science now got a solid base. https://papers.ssrn.com/sol3/papers.cfm?abstract_id=3039505

With some probability greater than zero.

Just was reading about Lockheed, remembered, decided to test. No, still not locked.

Will they now rename to Lockheed Martian?