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Thread: Will space debris make space exploration impossible

  1. #61
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    Maybe a big slab of aerogel to gather smaller bits at speed to lessen the need for fuel.

  2. #62
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    Many countries are already working on such a concept. China has already announced that they will be testing/launching their's by the end of this year.

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  3. #63
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    Quote Originally Posted by publiusr View Post
    Maybe a big slab of aerogel to gather smaller bits at speed to lessen the need for fuel.
    Aerogel's fine for collecting dust particles, but it's brittle and would produce more debris through fragmentation from the larger hits. You also can only ship up small volumes at a time.

    Better would be some kind of sticky low density foam, something that can be shipped up in liquid or compressed form and expanded in orbit to vastly larger size. Ideally, something with low vapor pressure components that will sublimate or disintegrate to particles of harmlessly small size over time, so fragments knocked off by larger impacts don't pose a long-term hazard themselves. You could ship a can of the stuff up with low orbit satellites and expand it at the end of their life as a disposal mechanism, increasing drag so the satellite reenters and collecting a good bit of debris on the way.

  4. #64
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    That sounds good--it looks like there is some tougher aerogel stuff coming out
    http://nextbigfuture.com/2014/06/sup...d-density.html
    http://nextbigfuture.com/2014/06/car...aphene-in.html

    Sounds more like solar sail material.

  5. #65
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    This is why I'm a proponent of global warming.

    Global warming will cause our atmosphere to expand, where it will create increased drag on orbiting debris, ultimately de-orbiting it.

    Who's with me!

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    India has announced a 3 min delay to launch their rocket carrying five foreign satellites on the 30th of June to avoid space debris

    http://www.ianslive.in/index.php?par...29959/NATION/1

    Chennai, June 27 (IANS) The Monday morning blast off of an Indian rocket carrying five foreign satellites has been delayed by three minutes to avoid a collision with space debris, the space agency said.

    According to Indian Space Research Organisation (ISRO), the Launch Authorisation Board (LAB) has given its nod for its expendable rocket Polar Satellite Launch Vehicle's (PSLV) flight on Monday morning at 9.52 a.m.

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    ISS has been hit by a space debri

    http://www.space-travel.com/m/report...gment_999.html

    Space debris has damaged a cooling system radiator of the International Space Station US, the NASA website said. Images of the ISS surface captured by external cameras were being analyzed and there was no leak from the cooling system.

    The NASA delegation to the Russian Mission Control Center has made no comment on the situation.
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  8. #68
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    I think you need some better news sources...
    The article says that NASA says according to some other news source who said NASA won't comment.
    Probably translated, again and again, and the ones who won't comment probably aren't even involved which is why they don't comment.

    A quick search shows the NASA source.
    The impact was found during a routine imagery over a week ago.

    Yes; this kind of strike is dangerous and of concern, but it happens often, and it's not necessarily man made debris.

  9. #69
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    It's inevitable. Those things are quite big.

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    It's likely future spacecraft and station habs will use expandable techs like what Bigelow and Thin Red Line (Canada) have been working on with NASA (and they've worked together on the Genesis testbeds.) This tech is inherently more impact resistant than aluminum tin cans, and most of the important bits are internal.

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    Quote Originally Posted by NEOWatcher View Post
    I think you need some better news sources...
    The article says that NASA says according to some other news source who said NASA won't comment.
    Probably translated, again and again, and the ones who won't comment probably aren't even involved which is why they don't comment.

    A quick search shows the NASA source.
    The impact was found during a routine imagery over a week ago.

    Yes; this kind of strike is dangerous and of concern, but it happens often, and it's not necessarily man made debris.
    They did say it was from the NASA site.
    It was the NASA delegation visiting Russia that had no comment.
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  12. #72
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    Quote Originally Posted by selvaarchi View Post
    They did say it was from the NASA site.
    Only because they said it in the VOR article.
    If they were actually reporting, they would have looked it up instead of summarizing someone else's story.

    Quote Originally Posted by selvaarchi View Post
    It was the NASA delegation visiting Russia that had no comment.
    That's my point. Why would they have knowledge of it. VOR should have gone straight from the NASA source since they already know it was reported there.
    Instead, they are more concerned about a sound bite from someone. Visitors were probably just handy at the time, so they didn't bother to go further.

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    Russia has plans to go something with satellites in GEO that are now dead.

    http://www.spacedaily.com/reports/Ro...utter_999.html

    The Russian Federal Space Agency (Roscosmos) is planning to spend 10.8 million rubles to develop a new spacecraft that would be used to remove space debris which is locked in a geostationary orbit, such as decommissioned satellites and used-up boosters, according to Izvestia.

    The agency intends to deploy the spacecraft, codename Liquidator, to clear up the geostationary orbit over the equator, which is 36 thousand kilometers above sea level.

    Satellites in this area, which is sometimes called the Clarke orbit or Clarke belt, appear stationary because they are locked in place relative to the Earth. As a result of this feature, the geostationary orbit is where communication and broadcasting satellites mostly operate.

    The Liquidator's parameters are listed in the Federal Space Program project for 2016-2025: the spacecraft will weigh four tons and be capable of removing up to 10 decommissioned craft and boosters from orbit per 6-month cycle. The space vehicle is expected to have an operating life of up to 10 years and it will be capable of performing at least 20 clean-up cycles.

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    Quote Originally Posted by selvaarchi View Post
    Russia has plans to go something with satellites in GEO that are now dead.
    Let's hope they go with the de-orbit idea. I never thought that the idea to move them to a parking orbit had anything to do with clearing up orbital debris. It just moves the debris (dead sats) out of a precious orbit and serves primarily to make room for new satellites.

    New satellites to GEO normally have the ability for parking at end of life. So; it's the older ones we are looking at.

    I also wonder if a better option would be to shoot them outside the Earth's gravity well. It seems to be more efficient than de-orbit. (Delta-V of >2.3 vs >3.8)

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    Quote Originally Posted by NEOWatcher View Post
    Let's hope they go with the de-orbit idea. I never thought that the idea to move them to a parking orbit had anything to do with clearing up orbital debris. It just moves the debris (dead sats) out of a precious orbit and serves primarily to make room for new satellites.

    New satellites to GEO normally have the ability for parking at end of life. So; it's the older ones we are looking at.

    I also wonder if a better option would be to shoot them outside the Earth's gravity well. It seems to be more efficient than de-orbit. (Delta-V of >2.3 vs >3.8)
    I would agree to move them out of earth's orbit. I would go one step further and recommend they be put on a path to burn up in the sun.
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  17. #77
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    Quote Originally Posted by selvaarchi View Post
    I would agree to move them out of earth's orbit. I would go one step further and recommend they be put on a path to burn up in the sun.
    That would require about 10 times the Delta-V of just escape.

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    Quote Originally Posted by NEOWatcher View Post
    That would require about 10 times the Delta-V of just escape.
    If it leaves earth's gravity influence will it not come into the sun's influence.
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    Quote Originally Posted by selvaarchi View Post
    If it leaves earth's gravity influence will it not come into the sun's influence.
    That just means it'll go into orbit around the Sun. Actually getting it to the Sun takes a lot more energy.
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  20. #80
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    Or to put it another way...
    For a Sun crossing orbit from Earth distance, it would have to be so eccentric that it's angular velocity at apogee (from Earth) would have to be near zero.
    Therefore, you need to shed most of Earth's 108,000 kmh velocity.

  21. #81
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    An object that just escapes Earth will end up in a very Earthlike orbit around the sun, you need an additional 30 km/s of delta-v to reach the sun. It was difficult to get a single probe to Mercury, dropping something into the sun would be an extremely expensive way to dispose of it.

    It would also be extraordinarily wasteful and quite unnecessary. The satellites are only a problem because they're occupying crowded orbits, there's no shortage of space to put them in. Dump them into a high disposal orbit, perhaps at an Earth-moon L4/L5 point, and they can be recovered and recycled at some later time.

  22. #82
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    Quote Originally Posted by cjameshuff View Post
    An object that just escapes Earth will end up in a very Earthlike orbit around the sun, you need an additional 30 km/s of delta-v to reach the sun.
    That's from LEO.
    From GEO you can subtract 3.8. (not that it changes the picture that much)

    Quote Originally Posted by cjameshuff View Post
    Dump them into a high disposal orbit, perhaps at an Earth-moon L4/L5 point, and they can be recovered and recycled at some later time.
    That's probably an even better idea. They are away from Earth by quite a bit, isolated in one area and at a loss of only 1.7 Delta V (less than half of de-orbiting)

  23. #83
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    Quote Originally Posted by NEOWatcher View Post
    That's from LEO.
    From GEO you can subtract 3.8. (not that it changes the picture that much)
    That's from any orbit. An object at escape velocity will slow to practically a halt with respect to Earth within a short distance on the scale of the solar system.
    1 AU is 499 light seconds...an object that leaves Earth at escape velocity will have slowed to 230 m/s with respect to Earth by the time it reaches 50 light seconds distance. The orbital velocity at its initial location just means you start out partway to escape velocity.


    Quote Originally Posted by NEOWatcher View Post
    That's probably an even better idea. They are away from Earth by quite a bit, isolated in one area and at a loss of only 1.7 Delta V (less than half of de-orbiting)
    And there are other choices that might be cheaper and just as effective...maybe a 2:1 resonance with the moon would be long lived enough for this purpose. The stuff doesn't need to be destroyed, just moved where it's not a collision hazard and debris source.

  24. #84
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    Just a wild idea. Will it possible to attach a solar sail on to the satellites to either make them come closer to the sun or move them further away?

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    A call to Rethinking Space Debris Mitigation.

    http://spacenews.com/article/opinion...ris-mitigation

    We should reconsider the scope and application of measures to mitigate space debris. The same constraints need not and probably cannot be imposed on all satellites.

    Space debris is a serious environmental threat. The consequences of collisions between satellites may be unacceptable. We must mitigate low-probability, high-consequence events.

    However, not all mitigation guidelines may be required for all satellites, and some classes of satellites cannot satisfy all of the guidelines.

  26. #86
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    Quote Originally Posted by selvaarchi View Post
    A call to Rethinking Space Debris Mitigation.

    http://spacenews.com/article/opinion...ris-mitigation
    In other words "OMG it's hard and it costs money".

    It's like any other environmental issue: there will always be calls to make exceptions when it constrains corporations' convenience or ability to make a profit.
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  27. #87
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    Quote Originally Posted by cjameshuff View Post
    That's from any orbit. An object at escape velocity will slow to practically a halt with respect to Earth within a short distance on the scale of the solar system.
    I guess I have a hard time understanding that, since I'm not that familiar with the math. While I can see what you are saying, the slowing is a transition from a highly elliptical orbit to a hyperbolic one.
    From GEO it's already a high circular orbit, so increasing from a GEO circular orbit just seems easier than from an LEO circular orbit. You've already spent Delta-V to make the orbit more eccentric than LEO, and again to circularize it.

  28. #88
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    Cubesat Revolution is causing a major problem with space debris. Reason - a sizable portion of them are paying little attention to the rule - to remove their hardware from low Earth orbit within 25 years after its mission. This article highlights the problem with no solution.

    http://spacenews.com/article/civil-s...fuel-dangerous

    The world’s rocket and satellite owners are doing a mediocre job in respecting debris-mitigation rules, especially in low Earth orbit, where debris proliferation is the ugly underside of the fast-growing small-satellite and microsatellite market, government and industry officials said.

    Twelve years after a grouping of the world’s space powers published what it thought were modest guidelines asking that satellite and rocket owners take steps to remove their hardware from low Earth orbit within 25 years after its mission, a sizable portion of them are paying little attention to the rule.

    The French space agency, CNES, studied 12 years of debris-mitigation practices, 2000-2012, and found that 40 percent of satellites and rocket bodies are left in low Earth orbit at altitudes high enough to make it impossible for them to re-enter within the 25-year window specified in the rules.

  29. #89
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    Quote Originally Posted by NEOWatcher View Post
    I guess I have a hard time understanding that, since I'm not that familiar with the math. While I can see what you are saying, the slowing is a transition from a highly elliptical orbit to a hyperbolic one.
    From GEO it's already a high circular orbit, so increasing from a GEO circular orbit just seems easier than from an LEO circular orbit. You've already spent Delta-V to make the orbit more eccentric than LEO, and again to circularize it.
    Ignoring the influence of other bodies, an object at escape velocity at one distance will be at escape velocity at every distance, which means it'll be practically stationary with respect to Earth after it gets a few light seconds away, no matter what orbit it started out in. Reaching escape velocity is easier from higher orbits, but my point was that just reaching escape velocity leaves you in an Earthlike orbit, 30 km/s away from reaching the sun.

    The velocity you actually need is the one that leaves you with 30 km/s of excess velocity after escape. If I've done the numbers right, that's 32 km/s from LEO, an added 21 km/s over orbital velocity, and 30.2 km/s from GEO, an added 26.2 km/s over circular orbital velocity. So it's actually more difficult by about 5 km/s to hit the sun from GEO, as compared to LEO.

  30. #90
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    NASA Team Proposes to Use
    Laser to Track Orbital Debris

    http://www.spacemart.com/m/reports/N...ebris_999.html

    Barry Coyle and Paul Stysley, laser researchers at NASA's Goddard Space Flight Center in Greenbelt, Maryland, want to develop a method to define and track orbital debris using laser ranging - a promising approach that could overcome shortfalls with passive optical and radar techniques, which debris trackers use today to locate and track dead satellites, spacecraft components, and other remnants orbiting in low-Earth or geosynchronous orbits where most space assets reside.
    Last edited by selvaarchi; 2014-Oct-30 at 09:53 AM.
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