Author Topic: Solar thermal garbage dispose satellite  (Read 738 times)

Online A_M_Swallow

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Solar thermal garbage dispose satellite
« on: 02/15/2012 09:06 pm »
Using a solar thermal satellite to remove old satellites was mentioned in the "Report Selects 16 Highest Priorities to Guide NASA's Technology Development".  This may have wondered off topic so I am starting a new thread for it.  I have copied the appropriate sections over.

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Re: Report Selects 16 Highest Priorities to Guide NASA's Technology Development
Reply #110 on: Today at 17:03:55
   
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Quote from: Solman on Today at 16:46:02

    The Phrase "not always going to be where solar is viable does itself imply that there are now places where it is - no?


SEP and STP effectiveness drop off past the asteroid belt and when mining underground.

If the concentrated light can vaporise aluminium it may be able to melt steel, copper and silicon - the rest of the satellite can be used as fuel.

The Swiss have proposed a clear up satellite to deal with the 16,000 significant sized objects in orbit.  That machine only de-orbits 1 item.  A garbage collection vehicle that eats dead satellites could dispose of several dead satellites.  This may provide a cost justification.
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Solman
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Re: Report Selects 16 Highest Priorities to Guide NASA's Technology Development
Reply #111 on: Today at 17:05:07
   
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Quote from: JohnFornaro on 14 February 2012, 20:05:49

    Quote from: Jim on 10 February 2012, 00:29:16

        Quote from: Solman on 09 February 2012, 22:03:03


             Imagine that a solar thermal/electric vehicle with a large concentrator mirror arrives at a random asteroid
             


        thought experiment fails right there, concentrator size is infeasible.


    Quote from: Blackstar on 09 February 2012, 23:39:13

        Quote from: Solman on 09 February 2012, 22:03:03

            Of course we must always assume that the experts have thought of everything and are always right.


        Can we see your engineering designs for this mission? It sounds exciting. What is your payload mass, and what are the power requirements?


    Quote from: Solman on 14 February 2012, 15:39:58

        I looked though the comments and I cannot find a technical objection made by Jim or Blackstar on technical grounds...


    It looks like Blackstar was first.  He asked to see your engineering designs.  It doesn't matter if he was serious or sarcastic.  Had you provided the engineering designs, every subsequent post of his would have been different.

    And Jim was second.  Any one of these devices has a size.  Size is the easiest technical issue to address, and you have still not addressed this issue, other than to discuss the size of an inflatable design that someone else got the funding to fly.

    You are the person who chose to conclude that these two objectors to your scheme were opposed to the idea of either "using large concentrator mirrors" or "using them for power propulsion and mining/refining".  However, you insist that you "don't see that as a technical objection to the design of the vehicle or mission".  The truth is more that you refuse to see their technical objections as technical objections.

    "Brainstorming is fun", and so are Aplle apps.  I can't speak for others, but for me, the brainstorming needs to be in a subject which interests me or applicable to one of those subjects, it needs to be informative, it needs to be realistic, and if it is mutually fun and enjoyable, then praise Calliope.  I would like to make a buck at what I'm interested in, ultimately.

    Quote from: Solman on 14 February 2012, 15:57:13

        I tried to enter inflation insitu-form with degradable elements in the NIAC solicitation that ended Feb. 9  but at the last minute found I had to be a registered organization - I sent it in anyway but I don't know if it got through.


    And since I'd like to make a buck, I took a look at that proposal myself.  I downloaded the document, and read the cover page, and the first page of the table of contents.  There I found the third thing that I needed to read: Section V Proposal and Submission Information; part (b) Propoasal Instructions and requirements, page 7.

    Quote

        Proposers are responsible for understanding and complying with its procedures for the successful, timely preparation and submission of their proposals.


    These requirements are incredibly complex, with all that registration information required, but I'm not the guy who's in charge of all that.  All I can say, is that I saw this in the first few minutes of reading; I didn't find out about it at the "last munute".  Am I weird for reading the proposal requirements first?  To see if I have a ghost of a chance?  Sure, "In short [you] have made effort", but it is insufficient.

    Get a job with L'Garde maybe?  'Cause you certainly believe in their approach.  Are you willing to relocate?

    I saw that elephant in the room picture.  Did you know that elephants paint their toenails different colors so that they can hide in jellybean jars?  Have you ever seen an elephant in a jellybean jar?  No?  The technique must work pretty good then.


 L'Garde has not succeeded in getting any further orders that I know of so what is your point?
 Your implication that I'm using false logic in your elephant analogy frankly baffles me - if I'm ignoring a particular technical problem state it. If the concept as a whole has a basic flaw please state that.
 Whether Blackstar was hostile to the idea or not it is safe to say that nothing indicated support. If only detailed engineering is allowed in the "Advanced Concepts" thread where may concepts be discussed?
 As to concentrator size - please read what I wrote - the important thing is whether the requisite temps can be achieved. A small concentrator - even a few feet in dia. may achieve them if mirror accuracy is adequate. A larger concentrator allows more to be done per unit time. I like big ones and so proposed a 100m dia. one for an example.
 If inflation insituform with degradable elements is indeed feasible then very large and very accurate mirrors of high accuracy are possible.
 As for making money - I called the concept "Bootstrap to Infinite Wealth didn't I?
 Ask Jim if he's opposed to this idea - his posts certainly suggest that would be a big yes. If he supports it that would be something he has carefully kept to himself.

Steve
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Solman
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Re: Report Selects 16 Highest Priorities to Guide NASA's Technology Development
Reply #112 on: Today at 17:06:57
   
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Quote from: A_M_Swallow on Today at 17:03:55

    Quote from: Solman on Today at 16:46:02

        The Phrase "not always going to be where solar is viable does itself imply that there are now places where it is - no?


    SEP and STP effectiveness drop off past the asteroid belt and when mining underground.

    If the concentrated light can vaporise aluminium it may be able to melt steel, copper and silicon - the rest of the satellite can be used as fuel.

    The Swiss have proposed a clear up satellite to deal with the 16,000 significant sized objects in orbit.  That machine only de-orbits 1 item.  A garbage collection vehicle that eats dead satellites could dispose of several dead satellites.  This may provide a cost justification.


 Thanks AM - I always have a smile on my face when I see that you've posted something and I'm never disappointed.

Steve
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Re: Report Selects 16 Highest Priorities to Guide NASA's Technology Development
Reply #113 on: Today at 17:10:18
   
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Quote from: Jim on Today at 16:50:36

    Quote from: Solman on Today at 16:46:02

        Quote from: Jim on 14 February 2012, 16:51:36

            Quote from: Solman on 14 February 2012, 16:40:22


                 BTW - What near term practical alternatives do you see to solar if you accept for the sake of argument that space ISRU development and industrialization IS a worthy goal?


            If it is a worthy goal, then it is not always going to be where solar is viable.

            Nuclear.

        You seem to be discounted the possibility of transmitting power by microwaves - a tech that large concentrator mirrors/antennas are ideally suited for.


    Not millions of miles


 Power need only be transmitted from something in the Sun to something that isn't - hundreds of miles at most or perhaps thousands if you're talking about a solar power sat in GEO. Large antennas make that feasible.
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Re: Report Selects 16 Highest Priorities to Guide NASA's Technology Development
Reply #114 on: Today at 17:31:18
   
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Quote from: A_M_Swallow on Today at 17:03:55

    The Swiss have proposed a clear up satellite to deal with the 16,000 significant sized objects in orbit.  That machine only de-orbits 1 item.  A garbage collection vehicle that eats dead satellites could dispose of several dead satellites.  This may provide a cost justification.


Yeah a solar-electric thruster that uses garbage satellites as propellant would be a beautiful thing for orbital debris removal. Such a garbage collector could keep collecting piece after piece of debris until something breaks.
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Patchouli
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Re: Report Selects 16 Highest Priorities to Guide NASA's Technology Development
Reply #115 on: Today at 19:56:58
   
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Quote from: Robotbeat on Today at 05:59:42

    It's not the IMLEO of the consumables themselves that are the problem. It's that you 1) have to store all that somewhere, that takes structure and space which both have a lot of mass and cost associate with them and 2) have to push all that (or much of it) through very large delta-vs using the exponential rocket equation. For the sprint missions, you have a REALLY high delta-v, so you're not necessarily saving any IMLEO compared to open-loop on a slow mission.


If I were to design a Mars missions I'd use the Ride report as a starting point and go with a split sprint class mission.
Here only the crewed parts of the mission go on the sprint class trajectories.

The rest such as lander return propellant etc can be sent ahead of time on a slower trajectory.
This really saves on the IMLEO payloads while still netting most of the benefits of a high delta V fast trajectory.
I'd probably go one one step farther in maximizing the LV's payload and have the cargo even use SEP for deporting LEO.

The crewed part takes the fastest possible route possible using chemical or NTR for departure and even SEP/NEP cruise.
The SEP/NEP propulsion should be sized to have enough delta V to allow an abort to Earth should something go wrong.


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JohnFornaro
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Re: Report Selects 16 Highest Priorities to Guide NASA's Technology Development
Reply #116 on: Today at 20:48:20
   
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Quote from: Solman on Today at 17:05:07

    L'Garde has not succeeded in getting any further orders that I know of so what is your point?
    Quote


        Just seemed like they were the only grup which have made something along the lines of what you propose; you are a fan of the concentrator concept; maybe there's a work opp there for you.  If they haven't gotten any further orders, and they've launched something, then how can you expect further orders yourself?

        Quote

            Your implication that I'm using false logic in your elephant analogy frankly baffles me -


        It's a dumb kindergarten joke.  Don't worry, tho.  Jim doesn't laugh at my jokes either...

        Quote

            ...if I'm ignoring a particular technical problem state it. If the concept as a whole has a basic flaw please state that.


        You haven't addressed the first flaw, size of concentrator with any semblance of significant attention.  100m can focus how much raw energy at various distances?  What percentage of that energy can you capture usefully?  What are you making and how much of it are you making?

        Depends on what you mean by the term "ignore".  You certainly appear to be ignoring the issues that have been brought up.  I'm starting to give curt answers because you are not demonstrating that you're listening, nor are you offering any believable support to your conjecture.

        Quote

            Whether Blackstar was hostile to the idea or not it is safe to say that nothing indicated support.


        There's nothing that I can see to support, except for your assertions, which are looking more and more baseless.

        Quote

            If only detailed engineering is allowed in the "Advanced Concepts" thread where may concepts be discussed?


        You seem to think that there are only two alternatives, baseless conjecture and detailed engineering.  There's a broad range between these two extremes.  Where have you gone beyond the stage of assertion?

        Quote

            As to concentrator size - please read what I wrote - the important thing is whether the requisite temps can be achieved.


        Wrong.  It's temperature, mass which can be handled, and capability of the mechanism, and a host of other things which I have mentioned.  These are dependent on diameter of concentrator, distance from sun, and efficiency of processing equipment.  Andrew Swallow mentioned melting points above; there's quite a range:

        Al Melting point, 933.47 K, 660.32 C, 1220.58 F

        Si Melting point, 1687 K, 1414 C, 2577 F.

        Fe Melting Point, 1535.0 C 1808.15 K, 2795.0 F

        W Melting point, 3695 K, 3422 C, 6192 F

        I give up.

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Re: Report Selects 16 Highest Priorities to Guide NASA's Technology Development
Reply #117 on: Today at 21:49:09
   
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Quote from: JohnFornaro on Today at 20:48:20


    Wrong.  It's temperature, mass which can be handled, and capability of the mechanism, and a host of other things which I have mentioned.  These are dependent on diameter of concentrator, distance from sun, and efficiency of processing equipment.  Andrew Swallow mentioned melting points above; there's quite a range:

    Al Melting point, 933.47 K, 660.32 C, 1220.58 F

    Si Melting point, 1687 K, 1414 C, 2577 F.

    Fe Melting Point, 1535.0 C 1808.15 K, 2795.0 F

    W Melting point, 3695 K, 3422 C, 6192 F


Thank you.

So providing the temperature of the concentrated sunlight is kept below 3695 K (- safety factor) then a garbage collection satellite with tungsten grippers can cut up even the steel parts of satellites.

Aluminium's boiling point is 2792 K, 2519 C, 4566 F.  To produce thrust the engine will have to work at that temperature.

I am enjoying this discussion but we may be off topic so it probably needs its own thread.

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