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For the record. So much of what you have stated above is so inaccurate that it makes it pointless to try and argue with you.

Example: You suggest that it would be easier to collect the debris than to deflect it into a decaying orbit. Do a little research and you will find that the 8000 or so tracked objects represent a total mass of approximately 3000 tonnes. Where you gonna put it? Some pieces are 20 metres in length.

Example: You suggest that it is "easy to dodge space debris". The 8000 tracked items represent only those pieces > 10cm. They are but the tip of the iceberg. There are estimated to be upward of 100,000 (maybe as high as 500,000) pieces 10cm<debris>1 mm. A "spec of paint" was enough to punch a pretty substantial hole in the "bullet proof" window of the space shuttle. How do you dodge something you have no idea is coming? (Not to mention that "station keeping fuel" is one of the major limitations upon the lifetime of a satallite.

For example. One of the major roles of the 1.3 billion Euro ATV, is to use it's thrusters to regularly push the ISS higher to compensate for its otherwise rapidly decaying orbit (Remember that discussion? So big objects don't decay due to atmospheric drag huh!)

I looked to refuting your blanket dismissal of the feasibility of the ideas I expressed above. It turns out that the math underlying Orbital Mechanics is far less onerous than I had thought--once you find the right source of practically, rather than theoretically expressed information. What eventually stopped me was the requirement to be an "approved registered user"(*) in order to obtain the basic data (TLEs) with which to construct a simulation. Well that, and the distinct impression that it wouldn't sway you one iota.

Al-Qaeda might nip up there and start throwing them at the US?

There are reasons why using a redundant space shuttle wouldn't be a good idea. None that you broached though. It's mostly to do with its mass. Regularly changing the orbit of so massive a structure, most of which would be redundant for the task, it too costly. However, that doesn't mean that it would make sense to use a to-be-retired-shuttle to put such a project into orbit.

And the Molinya orbit wasn't such a red-herring after all. For two reasons.

  • Firstly, a highly elliptical orbit is advantageous for this because it is much cheaper (in fuel) to alter the inclination of a satallite when it is further way from the Earth. Further away means slower velocity, mean less fuel to alter the inclination.
  • Secondly, the elliptical orbit takes the deflector across many circular orbits (the ones where most satellites tend to be stationed), and as you transition those circular orbits in the elliptical orbit, the angular velocity of both is the same. Ie. As you transition the path of those pieces of debris in the circular orbits, provided that you are moving in roughly the direction and inclination, the relative velocities will be minimal.

Some data

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

In reply to Re^19: "Practices and Principles" to death by BrowserUk
in thread "Practices and Principles" to death by ack

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    [Corion]: Yesterday I encountered an interesting data structure problem. I have a remote program that emits events, and my client listens for these events with one-shot callbacks, that is, I register the callback and if the event gets generated that callback ...
    [Lady_Aleena]: robby_dobby, every day. Chaos is my life with few controls.
    [Corion]: ... gets called once. The data structure for that is just a hash of arrays, mapping the event type to a queue of registered one-shots, and the first one-shot from the queue gets removed and called.
    [Corion]: But now I want to register a one-shot for two events, of which only one will arrive, so my data structure doesn't work anymore...
    [Lady_Aleena]: Corion, ouchy.
    [Corion]: (maybe I should write this up as a SoPW) - currently, the "most efficient" data structure I come up with is a single array which I scan for the first fitting one-shot. Not efficient but I don't expect more than five outstanding one-shots anyway
    [choroba]: can't you create a meta-key corresponding to the disjunction of the events?
    [robby_dobby]: Corion: Heh. This whole thing smells of Strategy Pattern or MVC pattern.
    [Corion]: And performance linear to the number of registered one-shots doesn't feel that bad. Maybe I should collect statistics on how many callbacks are outstanding ;)
    [Corion]: choroba: Yes, but the longer I thought about efficient hashes mapping the event type back to their callbacks, and how to keep them in sync, the more I thought that all that optimization might just not be worth it, even if it's horribly inelegant

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