Monday, May 16, 2016

Massive Topic List with Half-Finished Writings on Gravity Balloons

NOTE: extremely meta post follows.

Several past posts have been a dump of a large set of topics all balled into one. Now, I would like to do something different. I have used a text file as a staging area where I battled ideas against each other (in terms of where they rank in priority) and also just spitball ideas to see what sticks. While I still like to do these things, I'm depreciating the text file as a tool. I would rather keep the extremely premature ideas on the back of a napkin (or email draft), and use the blog itself as a better format for medium-low effort writings.

Even so, I still have that massive backlog of stuff that I never got to finishing. In my personal philosophy, I want to follow the open source model, and just let information free whenever there's no compelling reason not to. So here it is, my newly retired backlog:

If I'm too wordy in my general writings, then there won't be much of interest in there. Nevertheless, not everything is terrible, and I'm always somewhat taken aback when I read my old writings. It might be nice to polish it up and put it in a nicely displayed format (at least with working links). But let me just go through and dig a few things out of the dredges...

Small Gravity Balloons

 I attacked this concept from several different angles. One specific scale I was interested in was 1 km size asteroids, since these get closer to the NEA territory. Air pressure might still be used to resist against self-gravitation or some other uses, but exactly what is an open question.

Stability Topics

Nothing I've posted has come close to an exhaustive accounting of the stability topics which span from the gravity balloon part itself, to the internals, to the friction buffers. Then, multiply some of these by all the different size classes. Every problem you look at, you can probably think of at least five different mathematically simplified cases. Each one of those problems could have an enormous amount of analysis, and even radically different formulations.

Phobos Reference Values

The moon of Mars is just too interesting to give up on. But fairly small, and also close to the Roche Limit, this moon also presents a host of different mathematics that can complicate its scenario. In spite of that, there is still a strong motivation to give definite values for some kind of maximally populated colony.

Space Development Plan

Where does the gravity balloon exist within some kind of space roadmap? There are some efforts to make a detailed space development roadmap (I have one in mind that was on Kickstarter). These can offer an interesting starting place, but may be too near-term to have much connection to gravity balloons. The NSS also has some interesting roadmaps that involve extremely far-reaching development goals. I am interested in making an ordering. What is likely to happen before a gravity balloon is built? What is strictly necessary?

Cross-Structures in Artificial Gravity Tubes

Unlike most artist illustrations and typical guidance from 1970s era concepts, the artificial gravity tubes inside a gravity balloon would be extremely friendly for developers who want to build skyscrapers straight across the tube. In fact, it would be necessary if the mass was not evenly distributed (this is more important for gravity balloons, since the shielding mass isn't integral to the hull, making the livable structures relatively heavier compared to the walls).

Lower-Gravity Tubes and Microgravity Industry

Where would sewage processing happen? Probably in tubes that don't have the burden of friction buffers (accomplished by spinning at very low rates). This seems perfectly fine for algae and other smaller and easy to manage husbandry of animals, etc. What other industry (like shipyards) would happen in the microgravity (but not airless) space? Probably lots.

Procurement and Management of Air

I address "air" in the basic physical sense a lot, but the chemical realities of production of air is more challenging.

Other Agenda Items

These topics aren't in that list, because I've only recently been kicking them around:
  • Looking into the work by Dr. Forward in his 1990s (and hard to obtain) books
  • Of course, actually conducting the scaled experiment
  • Inner solar system asteroid Delta V versus mass map (not perfect math, but good-enough with some help from JPL pre-calculated data)


  1. Hey,
    I'm a very loyal reader of your blog and have been silently hovering over it since months. I am an aspiring science-fiction author, currently working on a book that's based on asteroid colonization. It's the background for the main story, but I still want to add elements of actual science. Would you be willing to spare some time and your extensive knowledge for my research work?
    I'd be honored to give you a major credit in my book when I publish it.
    So far, I am reading your every blog post to help myself as much as I can.

    1. Hey, sorry I left your comment unattended for so long. That sounds awesome! I feel like the sci-fi subject area of asteroid colonization could certainly use some more love. If you want to directly ask questions, you can email me at alan (dot) rominger (at) gmail (dot com).

  2. I am new here. Looks very interesting. Keep up the good work!

  3. Hello, I am also interested in this topic, for a book as well, I'm planning a more in depth science angle.

  4. Hello, I am also interested in this topic, for a book as well, I'm planning a more in depth science angle.

    1. Cool. If you have any questions, your best bet might actually just be to leave an open question as a comment, and I can either reply and break-out into a post if there's a great deal to say. Right now I'm working on describing some more options for the global heat transfer because I've seen some writings and illustrations about that recently.