Space Junk

Status
Not open for further replies.
E

eosophobiac

Guest
I wasn't sure where to post this, but I found it interesting. I've often wondered with the amount of stuff in orbit, why there aren't more collisions, etc. Now at least I have an inkling. Anyone else ever wonder/hear about this?<br /><br />Cataloging space junk<br />Working on the 'world's largest jigsaw puzzle'<br />(CNN) -- When space shuttle Discovery blasted off, it joined thousands and thousands of manmade objects orbiting Earth.<br />But should one of those objects hit the craft as it orbits at 16,000 mph, it could cause severe damage and a scuttled mission.<br />The shuttle crew is too busy to watch out for objects in Discovery's orbit, and because no traffic cops patrol space, tracking is the responsibility of the 1st Space Control Squadron (SPCS) of the U.S. Air Force Space Command, which operates the Space Control Center (SCC) inside Cheyenne Mountain Operations Center in Colorado Springs, Colorado.<br />The squadron is charged with detecting, tracking, identifying and cataloging all manmade objects orbiting Earth larger than 10 centimeters (4 inches) long.<br />"We kind-of liken it to working on the world's largest jigsaw puzzle," said Robin Thurston, a historical data analyst employed by the 1st SPCS.<br />There are plenty of pieces to the puzzle. Thurston said the squadron is tracking 13,400 objects, of which 8,800 are cataloged, meaning that the squadron has associated them with a specific launch. The other 4,600 are awaiting identification.<br />'Floating around up there'<br />When the space shuttle is flying, the squadron performs "collision avoidance analysis" for NASA.<br />To do this, the squadron plots "a theoretical box around the shuttle" that measures 10- by-10-by-40 kilometers (6.2-by-6.6-by-24.8 miles). If any of the objects intersects this theoretical box, the squadron sends its analysis to NASA, which determines whether to change the shuttle's flight path.<br />NASA has changed the shuttle's flight path 12 times since the SCC began performing its an <div class="Discussion_UserSignature"> <p> </p><p> </p> </div>
 
C

chriscdc

Guest
Newscientist has an interesting news article about the problems of space junk.<br /><br />http://www.newscientistspace.com/article.ns?id=dn8608<br /><br />Does anyone have any extra information about this problem, or heard of proposals to fix the problem.<br /><br />If they use ion engines or tethers and attach them to currently orbiting pieces of junk, perhaps this could open up a whole new market for orbital rockets in the ~10kg payload range.
 
N

nexium

Guest
Perhaps if we hit the debris, simultaneously, with the narrowest possible beams from ten powerful lasers on the surface, we can slow the peice of junk, so the new orbit intersects with Earth's atmosphere. We need perhaps 50 such costly lasers as half of them will speed up the peice, and some will be out of effective range.<br />The problem is each laser beam spreads in air until it is about one watt per square centimeter, which heats the peice only about one degree, which produces almost no delta v. If we can get the peice hot enough, the outgasing will act as a jet engine propelling the peice in the opposite direction. This has to be done quickly before the peice rotates, as out gasing in random directions produces very little delta v.<br />If we can determine the exact rotational rate, we can time the laser pulses, so they only hit one side of the peice, slowing the rotation, as well as the revelution, but this does not help much, as most peices rotate fast enough to outgas significantly for more than one revelution. On the optimistic side a sufficiently powerful set of lasers can deorbit 1000 peices of junk per hour. Please comment, refute and or embellish. Neil
 
H

henryhallam

Guest
How big a laser are we talking about here? Something like the Airborne Laser in a 747? I wouldn't mind working in the garbage disposal industry if I got to play with toys like that!
 
M

mlorrey

Guest
Private industry has taken initiative to add deorbiting thrusters to all upper stages in the last decade or more. I believe that there has been a similar mandate for government funded missions since the 1980's (it's been a handy excuse to get rid of a lot of valuable external tanks) that began life as an executive order by either Reagan or Bush 41.<br /><br />I cannot say whether nations with developing space programs are doing the same.
 
J

jschaef5

Guest
Space Junk seems like one of those topics where we can plan and hypothesize about ways of getting rid of it, but nothing will be put into place and actions taken until something disastrous occurs <div class="Discussion_UserSignature"> </div>
 
V

vogon13

Guest
LOL<br /><br />Wielding a 500kw laser to zap hamburger wrappers in the median . . . . . <div class="Discussion_UserSignature"> <p><font color="#ff0000"><strong>TPTB went to Dallas and all I got was Plucked !!</strong></font></p><p><font color="#339966"><strong>So many people, so few recipes !!</strong></font></p><p><font color="#0000ff"><strong>Let's clean up this stinkhole !!</strong></font> </p> </div>
 
V

vt_hokie

Guest
I deal with space junk every day! <img src="/images/icons/wink.gif" />
 
H

henryhallam

Guest
I think the majority of this stuff is below 600km or so, so it has a limited lifespan... perhaps realistically the best thing to do is to put measures in place to avoid creating lots more smallish pieces, and just "cross fingers and wait it out" until the existing debris comes down of its own accord.
 
C

CalliArcale

Guest
<blockquote><font class="small">In reply to:</font><hr /><p>Wouldn't blasting them with a laser (or any other weapon) just bust them into smaller peices going in far less predictable directions? Making them even more dangerous?<p><hr /></p></p></blockquote><br /><br />The idea actually isn't to break them up. It's to impart thrust on them. It's actually a rather clever concept. You fire the laser at the bit of debris you want to destroy, very carefully, until part of it heats up and starts to vaporize. This produces thrust. Produce the right thrust in the right place and the object will deorbit in a controlled fashion. It would involve careful targetting and a very good picture of how the object is tumbling, not to mention a fair amount of patience. <div class="Discussion_UserSignature"> <p> </p><p><font color="#666699"><em>"People assume that time is a strict progression of cause to effect, but actually from a non-linear, non-subjective viewpoint it's more like a big ball of wibbly wobbly . . . timey wimey . . . stuff."</em>  -- The Tenth Doctor, "Blink"</font></p> </div>
 
J

jschaef5

Guest
Is most of the space junk just small pieces that will eventually fall down, or is most of the stuff stuck in orbit up there? <div class="Discussion_UserSignature"> </div>
 
C

chriscdc

Guest
You can avoid the difficulties with the target spinning by using intense pulses of light (as shuttle guy said earlier). Each pulse will dump all its energy into the first few layers of atoms. These atoms will then be ablated before they can conduct much heat to the underlying surface.
 
C

CalliArcale

Guest
There's some of each. Some of it is really big -- spent rocket stages. Some of these are in pretty long-term orbits, and in fact account for a lot of satellite sightings. I've seen a few rocket stages with my own eyes, although of course you can't tell by looking. (They're just points of light.) I find out by getting pass predictions from Heavens Above. <img src="/images/icons/wink.gif" /> Nowdays, launch companies try to set things up so the rocket stages end up on suborbital disposal trajectories, but it used to be common to let your upper stage go into very nearly the same initial parking orbit as your payload. With no kind of deorbit motor, the spent stages would stay there for a long time.<br /><br />If you consider that almost the entire mass of an expendable launch vehicle (apart from its propellant) is thrown away, there's a heck of a lot of junk produced with every satellite launch. Payload fairings/shrouds, interstages, rocket stages (especially upper stages, kick motors, and so forth), shrapnel from pryotechnics.... A lot of stuff <i>intentionally</i> abandoned once it has served its purpose, and some of it is very sturdy, being designed to provide a high degree of reliability to its customers.<br /><br />They had this really cool animated video for the MER missions showing the mission from liftoff to rolling around the Martian surface. It did a great job of showing just how much stuff has to be discarded in order to get that rover safely onto the Martian surface. First it jettisons the boosters, then the first stage, then the payload fairing, then the second stage, then the kick motor, then the spacecraft bus, then the heatshield, then the backshell, then the parachute, then the lander with its airbags. It goes from this enormous Delta II rocket to this little robot tooling around the surface of Mars. It was slightly sobering to realize that. <div class="Discussion_UserSignature"> <p> </p><p><font color="#666699"><em>"People assume that time is a strict progression of cause to effect, but actually from a non-linear, non-subjective viewpoint it's more like a big ball of wibbly wobbly . . . timey wimey . . . stuff."</em>  -- The Tenth Doctor, "Blink"</font></p> </div>
 
H

henryhallam

Guest
<font color="yellow"><br />Is most of the space junk just small pieces that will eventually fall down, or is most of the stuff stuck in orbit up there?<br /></font><br /><br />It will all come down, eventually. The predominant factor in orbital lifetime is altitude at perigee (closest approach to the Earth), it goes something like:<br /><400km a few months<br />400-600km a few years<br />700km decades<br /> />800km centuries<br /><br />The other two main factors are density of the object - small, dense objects experience less deceleration from drag, so they stay up longer than lightweight ones with lots of surface area - and periods of solar activity, which leads to expansion of the upper atmosphere (not sure if this is solely direct heating or something magnetic) and consequently more drag, reduced orbital lifetime.<br /><br />I'm pretty confident about the above, but the following is mostly speculation:<br /><br />I think the majority of junk is in lowish orbits and fairly lightweight. But the most <b>problematic</b> objects might be things like leftover upper stages (and numerous associated small parts) in geostationary transfer orbits, since these will have a fairly long lifespan and cross lots of potentially useful altitudes. Fortunately these would all have low inclinations which might make them easier to avoid.
 
Z

zarnic

Guest
I was reading an article in the latest Archaeology mag that discussed an interview with Alice Gorman of Australia. She says there is over 10,000 pieces of 'space junk' still up floating around, including the old <i>Vanguard</i>. My question is, how the heck to we keep from hitting any? <div class="Discussion_UserSignature"> <p><em>Wisdom doesn't automatically come with old age. Nothing does - except wrinkles.</em> A. Van Buren, 1978<br />* <em>An unbreakable toy is useful for breaking other toys.</em>  -- according to Van Roy</p> </div>
 
M

MeteorWayne

Guest
First of all, Welcome to Space.com!<br /><br />Second of all, space is very big <img src="/images/icons/smile.gif" /><br /><br />Third, they are not all in one orbit. Some are in very high orbits, such as geosynchronous heights, some in mid orbits, and some in low earth orbit.<br /><br />Once you get beyond the outer fringes of the atmosphere (higher than where the ISS is) the orbits will pretty much last forever. So as long as nothing else crosses that particular orbit, there's no danger.<br /><br />Orbits near the ISS height don't last forever, because eventually the resistance from the atmosphere slows the object down enough that it's orbit decays until it burns up in the atmosphere.<br /><br />With all that said, it is very crowded in LEO (low earth orbit) and there is a lot of stuff there. We track the larger pieces with radar (and satellites by eye and telescope) and can take action to avoid them by moving our orbit.<br /><br />Particularly dangerous are the smaller chunks, too small to track by radar.<br />Things do get hit up there. IIRC, at least two satellites have been disabled by impacts with orbital debris, and the Chinese recently, very stupidly, intentionally destroyed one of their own satellites creating thousands of new pieces in orbit.<br /><br />The Shuttle orbiters have been hit several times by debris, fortunately small enough to do only minor damage, such as put pinholes in radiators (not the pipelines), and damage the orbiter windows requiring their replacement.<br /><br />All the rest is luck, and the fact space is very big <img src="/images/icons/smile.gif" /><br /><br />Hope this helps.<br /><br />Wayne <br /><br />Edited for clarity <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>
 
Z

zarnic

Guest
Help it does, and I TY. Z <div class="Discussion_UserSignature"> <p><em>Wisdom doesn't automatically come with old age. Nothing does - except wrinkles.</em> A. Van Buren, 1978<br />* <em>An unbreakable toy is useful for breaking other toys.</em>  -- according to Van Roy</p> </div>
 
3

3488

Guest
Here are a few articles & links that will be of interest.<br /><br />I agree MeteorWayne, what a braindead stupid thing the Chinese did, by destroying that<br />satellite & adding thousands of pieces of space junk.<br /><br />Various hardware hit by space junk. <br /><br />Risk of Space Debris.<br /><br />The Shooting Gallery.<br /><br />Hubble Space Telescope Solar Array impact ESA.<br /><br />IIRC, the very lowest Earth orbits are cleared out periodically by natural causes, as the<br />Earth's upper atmosphere expands & contracts due to the 11 year Solar Cycle.<br /><br />Andrew Brown. <div class="Discussion_UserSignature"> <p><font color="#000080">"I suddenly noticed an anomaly to the left of Io, just off the rim of that world. It was extremely large with respect to the overall size of Io and crescent shaped. It seemed unbelievable that something that big had not been visible before".</font> <em><strong><font color="#000000">Linda Morabito </font></strong><font color="#800000">on discovering that the Jupiter moon Io was volcanically active. Friday 9th March 1979.</font></em></p><p><font size="1" color="#000080">http://www.launchphotography.com/</font><br /><br /><font size="1" color="#000080">http://anthmartian.googlepages.com/thisislandearth</font></p><p><font size="1" color="#000080">http://web.me.com/meridianijournal</font></p> </div>
 
M

MeteorWayne

Guest
Thanx Andrew for the research.<br />I will excerpt a few focused statements.<br /><br />NASA's main source of data for debris in the size range of 1 to 30 cm is the Haystack radar. The Haystack radar, operated by MIT Lincoln Laboratory, has been collecting orbital debris data for NASA since 1990 under an agreement with the U.S. Department of Defense. Haystack statistically samples the debris population by "staring" at selected pointing angles and detecting debris which fly through its field-of-view. The data are used to characterize the debris population by size, altitude, and inclination. From these measurements, scientists have concluded that there are over 100,000 debris fragments in orbit with sizes down to 1 cm. NASA also collects data from the Haystack Auxiliary Radar (HAX), located next to the main Haystack antenna. Although HAX is less sensitive than Haystack, it operates at a different wavelength (1.8 cm for HAX versus 3 cm for Haystack) and has a wider field-of-view. <br /><br /> link <br /><br />===========<br /><br />An advantage to using an optical telescope over radar is that telescopes can more easily detect debris objects in higher altitudes, such as geosynchronous orbit. NASA has previously used two optical telescopes for measuring orbital debris: a 3 m diameter liquid mirror telescope, which is referred to as the LMT, and a charge-coupled device (CCD) equipped 0.3 m Schmidt camera, which is referred to as the CCD Debris Telescope (CDT). Currently optical measurement research of orbital debris continues with the MODEST, MCAT and NASS projects that are explained below. <br /><br /> link <br /><br />=================<br />Debris smaller than about 1 mm cannot be detected easily by ground-based radars or optical telescopes. Space-based in-situ measurements have been the only means to characterize sub-mill <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>
 
M

MeteorWayne

Guest
Hey, zarnic, thanks for starting this thread. I know Andrew and I have learned a lot from our research, hopefully you have, and the SDC community has benefited from your question.<br /><br />Not bad for one of your first few posts!!<br /><br />Wayne <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>
 
P

pyoko

Guest
I've always wondered what the smeg is this so-called (and very common) 'space junk'? And how does it stay in orbit for so long. <br /><br />edit: typo corrected <div class="Discussion_UserSignature"> <p> </p><p> </p><p><span style="color:#ff9900" class="Apple-style-span">-pyoko</span> <span style="color:#333333" class="Apple-style-span">the</span> <span style="color:#339966" class="Apple-style-span">duck </span></p><p><span style="color:#339966" class="Apple-style-span"><span style="color:#808080;font-style:italic" class="Apple-style-span">It is by will alone I set my mind in motion.</span></span></p> </div>
 
M

MeteorWayne

Guest
"she smeg "????<br /><br />I must admit, I have no idea of what words you intended.<br /><br />In any case, something in orbit will stay there until acted on by an outside force.<br /><br />For lower orbits, that is interaction is with the outer wisps of the atmosphere. Hence they lose speed, the orbit decays, it dips deeper into the atmosphere, loses more speed, heats up, etc, until it burns up, or if it's a large, hard, high melting temperature material, what's left over hits the ground.. Once above 1000? km, there is no other force than the Sun, moon, and planets, and such orbits are stable for thousands or hundreds of thousands of years.<br /><br />That is the definition of an orbit. <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>
 
3

3488

Guest
Hi MeteorWayne,<br /><br />Thank you so much again, for you consideration & kind comments about me. <img src="/images/icons/laugh.gif" /> <img src="/images/icons/laugh.gif" /><br /><br />Those in Geostationary Orbit could persist for many millions of years. Of course the<br />Geosynchronous nature will not last, but because of their very large distance <br />(35,880 KM / 22,800 miles), will not suffer from orbital decay. <br /><br />Even when the Sun turns into a Red Giant, the Earth's atmosphere will not extend that far,<br />as it is driven away.<br /><br />Tidal influences WILL affect them, primarily from the Sun & Moon, perhaps over far longer <br />periods, by Venus & Jupiter also. <br /><br />I think we have stuff in High Earth Orbit that will remain in orbit for millions of years, as atmospheric <br />drag is not applicable that far from Earth.<br /><br />Perhaps erosion from micrometeoroid impacts will eventually destroy them.<br /><br />Unlike the ISS that requires VERY frequent orbital reboosts & even the <br />Hubble Space Telescope, which orbits far higher than the ISS, still needs to be 'lifted'<br />into higher orbit by the STS during servicing missions.<br /><br />Hi zarnic,<br /><br />I second MeteorWayne's thanks for starting this thread, & share his<br />admiration for you to start such an interesting thread, so soon after joining SDC. <br /><br />Andrew Brown. <div class="Discussion_UserSignature"> <p><font color="#000080">"I suddenly noticed an anomaly to the left of Io, just off the rim of that world. It was extremely large with respect to the overall size of Io and crescent shaped. It seemed unbelievable that something that big had not been visible before".</font> <em><strong><font color="#000000">Linda Morabito </font></strong><font color="#800000">on discovering that the Jupiter moon Io was volcanically active. Friday 9th March 1979.</font></em></p><p><font size="1" color="#000080">http://www.launchphotography.com/</font><br /><br /><font size="1" color="#000080">http://anthmartian.googlepages.com/thisislandearth</font></p><p><font size="1" color="#000080">http://web.me.com/meridianijournal</font></p> </div>
 
P

pyoko

Guest
Thanks guys. That answers one question... but what 'the smeg (on Earth/ in Hell, from Red Dwarf, the show)' is space junk? I don't believe 100 000 pieces of metal 'fell off' from launches. Or did they? <div class="Discussion_UserSignature"> <p> </p><p> </p><p><span style="color:#ff9900" class="Apple-style-span">-pyoko</span> <span style="color:#333333" class="Apple-style-span">the</span> <span style="color:#339966" class="Apple-style-span">duck </span></p><p><span style="color:#339966" class="Apple-style-span"><span style="color:#808080;font-style:italic" class="Apple-style-span">It is by will alone I set my mind in motion.</span></span></p> </div>
 
3

3488

Guest
Well, its pieces of old satellites, old satellites, paint chips, exploded upper stages, spent upper stages, etc.<br /><br />So 100,000 pieces may not be far off.<br /><br />Andrew Brown. <div class="Discussion_UserSignature"> <p><font color="#000080">"I suddenly noticed an anomaly to the left of Io, just off the rim of that world. It was extremely large with respect to the overall size of Io and crescent shaped. It seemed unbelievable that something that big had not been visible before".</font> <em><strong><font color="#000000">Linda Morabito </font></strong><font color="#800000">on discovering that the Jupiter moon Io was volcanically active. Friday 9th March 1979.</font></em></p><p><font size="1" color="#000080">http://www.launchphotography.com/</font><br /><br /><font size="1" color="#000080">http://anthmartian.googlepages.com/thisislandearth</font></p><p><font size="1" color="#000080">http://web.me.com/meridianijournal</font></p> </div>
 
Status
Not open for further replies.

ASK THE COMMUNITY