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Space is vast and lawless. Private travel is commonplace, and pirates have become a significant problem. People mainly fly orbit-to-orbit craft that have chemical rockets and no one is running around at relativistic speeds. How do you deal with space debris? One destroyed satellite created huge amounts of debris, so every cool space battle would be a disaster. I'm mostly looking for solutions that could be implemented by individuals - there isn't a strong enough government for a unified effort to reduce the amount of debris.

Edit:

I'm looking for non-govt/military solutions - they need safe transit too, but that's not the focus of my question. Getting to Mars takes variable amounts of time, depending on where it is in its orbit, and where you are. Maybe nine months from earth, if you left at the right time. People travel for the same reasons they always have, family, opportunities/jobs, etc... The solution has to be either low-cost - so average people can implement it on their own - or high cost, and spread out - like the 'toll road' and 'insurance company' ideas below. Ideas of the former category are preferred, but practicality is more important to me.

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  • $\begingroup$ If no one is traveling at relativistic speed, how long does it take to get to Mars? And why is it commonplace? For profit? What kind of profit? This info is relevant, because it'll show who will care, and who might pay. Amount of money and access to technology (especially military) may affect answers. $\endgroup$ – Mołot Oct 16 '16 at 17:52
  • $\begingroup$ Edited question - does this clear things up? $\endgroup$ – Charles Noon Oct 16 '16 at 19:07
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I believe there will be many lines of defense:

Tracking (agency)

All space debris of significant size (like single screw) is tracked now. It'll get more expensive, so NASA or whatever agency will replace it will have to charge for access to their data. Cheap captains/companies may try to buy one set a year, or after each significant battle, and compute everything on their own in the meantime. Big companies will probably have a daily subscription with emergency updates. First thing? Do not be where the debris is.

A ticket for littering

No joke here. Anyone caught at littering will be fined by Earth or Mars government. Intentional creation of debris will send someone bankrupt in no time. "Space Police" would track vessels involved in littering. Will know where they landed. If space station refuse to arrest such vessel will be fined, or put on serious embargo to make it not useful and it's inhabitants' lives miserable.

Cleanup by agencies

e.Deorbit is planned for 2021. Other agencies has their plans, too. financing? Of course taxpayers, launchpad fees. In other words, nothing new here. Well, maybe except space littering tickets, these should be use to pay for removal.

Tracking (on-board)

There is no stealth in space. And debris do not try to hide at all.

Imaging Radar Alone, or jointly with the Max-Planck-Institute of Radio Astronomy’s 100 m telescope at Effelsberg in Germany (bi-static mode), snapshots typically of 24 hours duration can be taken of the current space-debris population to provide statistical information and rough orbit parameters for objects as small as 1 cm at altitude up to 1000 km.

 

Creating Beam Park In this operating mode, the radar beam is maintained in a fixed direction with respect to the Earth and all objects that pass through the beam are registered. In the course of one day, the Earth’s rotation scans the beam through 360 deg in inertial space. From the backscattering of the radar signal, the size of the object and some of its orbital parameters can be determined. The FGAN radar is sensitive enough to detect 2 cm sized objects at a distance of 1000 km. This primarily statistical information on the small-size terrestrial debris population in the LEO (Low Earth Orbit) region can be used to validate space-debris models.

source

You want both 1cm minimal size of an object. And you want as long distance as possible. What you do not want is 100m telescope or having only statistical information. But improvements can be made, especially when you do not have any atmosphere to overcome.

Again, as in first line, once you know it's there, you can adjust your trajectory to avoid it.

Lasers

Objects under certain size are effectively harmless, because you want to be safe from micrometeorites anyway and spaceships are built to withstand micrometeorite hit. Heat one point of debris enough to turn it into gas, and you'll change it's trajectory. Hopefully in a way that will make it miss you. And if you break it in half in the process? Hey, it's twice the tracking, but half the momentum! So chances next vessel will survive hit by one of the parts are somehow increased.

Probably, captain could also claim a small reward if he could prove he used it in a Laser Broom way, deorbiting some debris.

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Kessler syndrome is only a problem for orbiting spacecraft

This is a common misunderstanding of the Kessler syndrome. Space is still incredibly big and incredibly empty. It's only objects that spend all their time in orbit that are likely to collide with something sooner or later.

To take some numbers, imagine Earth Orbit is so full of debris that a satellite in orbit has a 98% chance of colliding with debris within a month of launch. (for reference, the current rate of satellite destruction is approximately 00.004% per month).

Now think about how long a chemical rocket stays in Earth's orbital zone before it's out in the (relative) emptiness of space (clue: it's measured in minutes).

So, 1 month in space = 98% chance of colliding with debris.

Therefore, 1 day in space = 3% chance of collision.

1 hour in space ~ 0.1% chance of collision

And 6 minutes in space ~ 0.01% chance of collision.

Given that spacecraft are probably bigger and better shielded than your average satellite, and have access to systems which track large objects in earth orbit, orbital debris is just not going to be a meaningful problem.


Space battles are even easier. Space is mindbogglingly big. The distance from earth to mars is measured in tens of millions of kilometres. So a few tens of thousands of cubic kilometres out in the middle of the solar system had a big battle and created a ton of debris. Just fly a million miles around it. And within a week, that debris will be so spread out in space that it's indistinguishable from common space debris that every ship deals with as a matter of course.

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    $\begingroup$ True, but as you mentioned, Kessler syndrome would make staying in orbit hard. As specified in my question, these are orbit-to-orbit craft. They don't launch from or land on the surface. Still - this is very useful information! I hadn't realized that only space-battles close to planets would be a problem - thanks! $\endgroup$ – Charles Noon Oct 17 '16 at 0:39
  • $\begingroup$ So even an orbital craft with active control can just avoid stuff; same principle. You just need to have it well charted and tracked. $\endgroup$ – JDługosz Oct 17 '16 at 4:42
  • $\begingroup$ @CharlesNoon And your spacecraft can always orbit further way from earth. Kessler debris is only likely to exist (in large concentrations) in satellite orbits. Your spacecraft can just sit out beyond GEO where it's relatively clear. $\endgroup$ – Kaz Oct 17 '16 at 9:44
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    $\begingroup$ "Space..." it says "...is big. Really big. You just won't believe how vastly, hugely, mindbogglingly big it is. I mean, you may think it's a long way down the street to the chemist, but that's just peanuts to space! Listen..." The Hitch-Hiker's Guide To The Galaxy $\endgroup$ – MichaelK Oct 17 '16 at 11:14
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Private companies would clear out proprietary passages through the debris and use the threat of force against unauthorized users (or some legal acknowledgement of their right, perhaps in a court decision if the legislative process was immobilized) to pay tolls or tariffs that finance the clean up of their passage. They could also regulate what is and isn't allowed in trade like a border control station.

Multiple companies could compete doing this, perhaps an oligopoly that collective controls access to the surface, or worse yet, a tyrannical monopoly - perhaps because it costs a lot to keep the equipment necessary to keep it all running in trim shape under a declining civilization conditions.

They would not be perfectly successful at keeping their own routes clear, and the consequences when they fail could be a plot point. "Smugglers" could exploit natural and less well cleared paths at higher risk and prices.

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  • $\begingroup$ I really like this idea. It would make for a very interesting universe. I'll accept your answer if no one has any better ideas. (I don't have the rep to upvote you, unfortunately). Still, how would these companies keep track of 11km/sec paint flecks? Also, it seems that rather than "passages", companies would sell limited access to their database of known space debris. You would buy a one-time route to Mars, say, and the company would tell you when, where, and for how long to fire your engines. $\endgroup$ – Charles Noon Oct 14 '16 at 21:43
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    $\begingroup$ That doesn’t make sense. Different orbital heights have different speeds. There is no fixed “path” as everything is moving relative to everything else! $\endgroup$ – JDługosz Oct 15 '16 at 6:53
  • $\begingroup$ Yes, I think you'd end up with more of a 'one time route' situation, like I described in my comment above. $\endgroup$ – Charles Noon Oct 16 '16 at 17:41
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You'd have to send people out to clean it up. That's the only thing that wouldn't just make a bigger mess.

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Insurance companies would start putting out tenders for contractors to "sweep" space and reduce or eliminate space debris in order to avoid having to make massive payouts whenever a spacecraft is destroyed.

Depending on what is being bid on, the "Kepler cowboys" could use a wide variety of devices and means to clear space debris, ranging from "laser brooms" to complete spacecraft designed to match orbits and capture large pieces of space debris. Large balloons filled with water ice could be sent on eccentric orbits and small pieces of debris would impact the satellite, either stopping inside the iceball or slowing down enough by the passage through the ice to deorbit or go into a radically lower eccentric orbit.

The insurance companies will accept bids based on the reputation of the bidder and if the cost is lower than the projected losses of payouts to spacecraft and satellite operators.

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  • $\begingroup$ This is a neat idea, but I don't know how realistic it is. IRL, auto insurance companies don't pay people to fix potholes in roads. It seems that the result of risky space travel would just be higher insurance premiums. $\endgroup$ – Charles Noon Oct 16 '16 at 17:52
  • $\begingroup$ When a single claim could be over a billion dollars, insurers will probably take a different view of things. Municipal fire departments largely supplemented volunteer fire departments because of the insurance industry wanting to reduce claims for fire damage, for example. $\endgroup$ – Thucydides Oct 16 '16 at 20:10
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It seems to me that spacecraft would need systems to protect themselves from high speed projectiles in any case, if they plan on continuing to operate in space for long periods of time.

They need sensors (e.g., lidar) that are monitoring every potential threat at great distances (perhaps as much as 30 or 40,000 kilometers). They need artificial intelligence to analyze this massive amount of data, and to automatically detect and destroy or avoid any high speed projectile.

This sort of system would help them to navigate through the space junk in the vicinity of Earth, but it would also be useful anywhere in space.

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  • $\begingroup$ Neat - this definitely fits my "Solution Implemented by Individuals" criteria. I don't know much about lidar - what limitations does it have on size/speed of detected objects? I don't think AI would be necessary, though you would need some pretty powerful computers. Dodging would probably be easiest, destroying debris would be expensive and likely create more debris. $\endgroup$ – Charles Noon Oct 15 '16 at 0:13
  • $\begingroup$ I am imagining some future version of lidar, a light speed sensor that can scan a sphere the size of a planet and determine the position, velocity and acceleration of every body down to the size of a bullet. By "AI" I mean 2016 era machine learning AI technology, on larger, faster parallel computers, making choices about how to keep the ship safe, based on first principles and the shared experience of all the ships in space. $\endgroup$ – Charles Gillingham Oct 15 '16 at 2:20
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The debris will tend to form a belt around the equator, as this is the tendency of an interacting particle system and because most satellites were that way in the first place.

So it will be significantly clearer to launch upward from a pole, and get away from the Earth and not try to orbit Earth. Continuing needs for satellites will be filled by placing them much higher: beyond the bulk of the debris belt, and where orbits are moving much slower as well so the danger is less.

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  • $\begingroup$ Interesting idea, I hadn't thought of that. Still, how long would it take debris to condense in this way, especially if new debris is being generated by the occasional space battle? $\endgroup$ – Charles Noon Oct 16 '16 at 17:45
  • $\begingroup$ low orbit debris regularly orbit near poles. Maybe polar launcher are happen less often, but polar orbits intersect there. Also I have doubt about tending to form a belt. Interactive 3d map of debris, you may take look yourself stuffin.space $\endgroup$ – MolbOrg Oct 16 '16 at 21:16

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