With today's technology could mankind create a system of rings similar to Saturn composed of different masses of water particles and silicate minerals that would freeze? How could mankind accomplish this feat of engineering?
UPDATE: It looks like This question has been asked before, with pretty much the same sort of answer.
Well, ignoring the big question of "WHY?":
Using the same method that formed Saturn's Rings
Wikipedia is fairly detailed regarding the composition and formation theories for Saturn's rings. They all involve the disintegration of a Moon, either through being ripped apart due to getting too close to the planet (Roche Limit), or due to collision with another object. This would be preeetty difficult to replicate as you'd have to get an object of sufficient mass to create the rings into a close enough orbit, but only deteriorating slowly enough that it gets ripped apart rather than crashing into the planet and causing the apocalypse. That wouldn't be so good.
The alternative would be to smash something into the Moon and see what happens, but the dispersal would involve a bit of pot luck to give you the rings and again, may cause massive damage to the planet.
Either of the above seem pretty unlikely. Both of the methods above are beyond our current technology (short of nuking the moon and getting lucky), and there's no guarantee that either would work. I also seem to remember reading that Saturn's rings require "Shepherd Moons" in order to maintain their exact form - without the existence of some of Saturn's moons within the rings themselves, they would lose formation (If I'm wrong on that, someone correct me!).
There is however a third option, which wouldn't be exactly like Saturn's rings, but it might be close enough:
Have a look at This:
That's a picture of the space debris ALREADY in orbit around the Earth — not only that, but that image is over 10 years old. With a bit of shunting and maintenance (ok, a lot of shunting and maintenance), all of that debris could theoretically be aligned into a single plane, forming what would look an awful lot like Saturn's rings as the density of material on that plane was increased.
Interestingly, this also provides a reason for the "Why?": There are already serious issues trying to get stuff into orbit because of collision threats with space debris. If you could restrict debris to a single plane it would provide vastly greater launch windows, you wouldn't have to worry so much about debris shielding for launch, and it would theoretically prevent the Kessler Syndrome ever becoming reality. Plus, it would look pretty.
There would obviously be issues to content with — safe paths for satellites orbiting on intersecting planes, for instance — but it's theoretically far more feasible than actually creating Saturn's rings. As for the technology involved:
- The debris is already all tracked - that image is a computer model based on tracked debris, so they know where it is at the moment.
- Advanced knowledge of mechanics and physics would give you the ability to calculate the required force to redirect an object onto a different orbit - "Mankind" can certainly already do this
- Actually getting everything onto the new orbit would be the challenge. It would take an awful lot of time and an awful lot of manoeuvrable spacecraft, plus some method of "Sweeping up" the small stuff and transferring it to the new orbit wholesale.
- We'd probably need to have some way of keeping it there. Saturn's rings have been around for billions of years, we can't tell how much originally drifted away or into Saturn, neither of which are cases that we can afford.
The first two bits (planning it) are well within current technology. The Latter two, I don't know. Possibly, but it would require a massive amount of planning and resources, not to mention coordination between global powers! There is certainly tech to be created (like that sweeping brush) for which the physics would be tough, but not beyond human ingenuity, I would think. It'd just need a plausible enough reasons to get the money and people behind it.
Creating a temporary ring is relatively simple, and most of the previous posters have provided useful answers. The problem isn't so much that you can make a ring, but how to make it a stable structure in orbit around a planet.
Many of the rings of Saturn have been observed to have small moons whose orbits define the edges of various rings or gaps. The gravitational interplay between the various moons, particles in orbit and Saturn have pushed the particles into the rings we see, and have kept them stable over the eons since they were formed. Doing the same for Earth will be a bit tricky, since unlike Saturn, Earth has a single huge moon orbiting it, and it is quite possible that the perturbations caused by our moon will upset the intricate orbital dances between the tiny shepherd moons, the rings and the Earth.
This can be overcome if the builders take the time and expend the energy to actively "fly" the moons in accurate orbits using some sort of impulse to overcome perturbations caused by the Earth's natural satellite. Since this is a long term project, the shepherd moons will need to be propelled by some sort of passive system like Solar Sails, otherwise the energy and reaction mass requirements become prohibitive.
The moment the builders are no longer able or willing to take care of their creation, the shepherd moons will start to drift out of position and the ring system will begin to dissipate. Depending on initial conditions, this process could take centuries.
Launching stuff from the planet to orbit is expensive.
And if we want to do some major planet colonizing some day we're going to need to build a lot of ships and that means a lot of launches with a lot of equipment from Earth, unless we start manufacturing in space.
So pull in some raw materials in the form of captured asteroids and comets, and launch a couple small factory robots to start building the big factories.
Some of the existing junk would be pulled in and recycled instead of just letting it burn up.
All this manufacturing would produce dust and ice crystals, and over time these would build up until rings started to form in the orbits of the factories.
With all of the junk confined to these rings, maneuvering around the planet gets a lot easier.
Stealing from the Asteroid Belt
One option would be to 'borrow' the required mass from the asteroid belt between Mars and Jupiter - no easy feat for sure, but something current space agencies have plans to do, albeit on a much smaller scale.
Saturn's ring system has an estimated mass of 3 x 1019 kg, with Saturn's mass being ~ 6 x 1026 kg. Using Earth's mass of ~ 6 x 1024 kg, this gives us a ballpark Earth-Ring mass of 3 x 1017 kg. This gives us a ring system of a similar density and relative size to Saturn's.
Luckily for us, the asteroid belt is estimated to have ~ 3 x 1021 - enough for 10,000 rings! Now we know there's enough material, let's get started!
How to do it
Build an unmanned drone ship capable of sustained spaceflight for many hundreds of years with enough fuel for frequent burns. The burns don't necessarily need to be be powerful, so it's possible that this could be achieved with an ion engine. The size of the ship shouldn't matter in theory, but the bigger (more massive), the better!
Pick an asteroid, fly close by and use the gravity of your ship to nudge the asteroid into a transfer orbit to coincide with Earth. This will need to be done very precisely as we want the asteroid to fall in an orbit around Earth, not fall into Earth itself! By dropping the asteroids below Earth Roche limit, they should break apart and form perfect rings (should - no promises). Rinse and repeat!
Bonus: As other answers have mentioned, Saturn's ring system is kept in check by small shepherd moons. If you pick a large enough asteroid and place it in orbit above the Roche limit, you have a ready-made shepherd!.
Saturn's Rings are believed to consist almost entirely of water ice, whereas asteroid belt objects are typically carbon or metal-heavy. This means your rings will likely be less reflective than Saturn's.