19 thoughts on “The Rings Of Earth”

  1. That’s beautiful, but wouldn’t the Moon (being so massive compared to the moons of Saturn) disrupt and possibly disperse the rings? In any case, rings of Earth wouldn’t have gaps like those of Saturn, which are caused by resonances with Saturn’s moons. Finally, I suspect the albedo of any terrestrial ring system would be much lower than the rings of Saturn since they’d have to be composed of rocks, not ice.

    And still, what a project! I can see a post-singularity Christo doing it even if it only lasted a few months, just because it would be cool.

    1. I suspect the albedo of any terrestrial ring system would be much lower than the rings of Saturn since they’d have to be composed of rocks, not ice.

      No, they’ll mostly be aerospace grade aluminum.

  2. Cool, I think, is the correct word indeed. What would the climate effect be of such a ring blocking a significant percentage of sunlight? In the hemispheres undergoing winter at the time?

    Brrr!

    1. I wondered about that and the daylight summer cooling too. Overall, it looks like a big sun shade to me.

      I also wondered about reflected light at night. It seems like it would never get darker than twilight given the amount of reflected light, depending on what is in the rings.

      How would more light affect crime? There are fewer break ins and street crimes that require dark places during full moon. Maybe it would be a good thing?

    2. In Piers Anthony’s novel Rings of Ice (1974), iirc, the rings were made primarily for shade. (Then they decayed, becoming rain.)

      In the Madrid picture, the rings obscure the clouds, which of course is backward.

  3. If we made the rings out of little balls that could monitor their relative position and change their color in response to ground commands, the rings could display advertising.

    There’s also no reason the rings would have to be equatorial. Any orbital plane would work, and the ecliptic plane would make somewhat more sense regarding lunar perturbations.

    1. Sorry, no, George. any plane other than equatorial will have different rates of drift in right ascension at different altitudes, so the rings would rapidly become a large mass of collisions. Ring planes have strong feedback that forces them into the equatorial pane.

  4. The video seems to assume the same distance/width scale as seen with Saturn, but wouldn’t rings around Earth be at a different distance from the planet due to the gravitational differences? At the distance shown, they’d play havoc with the ISS, HST and other satellites, no?

  5. The video said that they took Roche limits into account. I’m not clear what that means. Wikipedia has a nice article on Roche limits, and maybe he had the outer boundary of the ring at the Roche limit, but I didn’t see what density he used for the particles to compute that. I don’t know how you’d set the inner edge–a few hundred km up to get it out of atmospheric drag?

  6. Anyway, the Roche limit is directly proportional to the radius of the body and to some power (cube root, roughly) of its density. If you assumed that the ratio of the density of the rings to the density of the planet was the same between Saturn’s rings and Earth’s rings, then the ratio of the diameter of the rings to the diameter of the planet would be roughly the same.

  7. But Saturn is really really less dense than Earth, right? In water, Saturn would float. So to maintain the ratio, the Earth rings would have to be made out of…what? Lead? Plutonium?

    1. Saturn’s rings are mainly ice, so maybe they’re 30% denser than Saturn. Earth has a density of 5.5, so if the rings had a density of 7.5 or so they’d have the same ratio. Somewhat less dense than iron. But even if Earth’s rings were made of Al, the cube root in the equation does a lot of flattening–they’d still be 70% or so the relative size of Saturn’s.

  8. The Earth is already surrounded by a cloud of orbiting space junk. Let’s build giant Space Roombas to sweep all the debris into nice neat rings.

    1. Flying sharks with lasers. They can zap the leading edge of wayward satellites as they cross the equatorial plane; the vaporizing metal provides an impulse to the satellites to change their inclination.

Comments are closed.