"Space" in Space (Kessler Syndrome question)

[18-Till-I-Die]

This idea just kind of popped up when i was writing something, and i know this probably sounds retarded, but anyway...

See i was writing this story wherein one of the conceits is a massive level of space infrastructure and development in the relatively distant future, and i recalled somewhat hazily something i had come across which the idea was that if enough "stuff" were in orbit, it would make going to space either difficult or impossible (the Kessler Syndrome, or some such).

But that's the thing...in this story, we have multiple, large space stations in immediate Earth orbit, as well as the expected L4/L5 stations and a moon base. So my question is, how much can we put in space--assuming you include the whole Earth-Moon "system" is it even possible to "clutter up" space? I just had a hard time imagining that much...space being filled up in any appreciable way.



And yeah, i realize the immediate response is probably "What are you drunk" but i needed to ask because i honestly don't know. The fact i'm drunk has nothing to do with it.

[Junghalli]

Well, the main problem you have to worry about isn't so much clutter as stuff drifting into chaotic orbits when stationkeeping propellants run out, or when somebody just carelessly chucks something out the airlock. Given that at orbital velocities even small bits of stuff are rather dangerous KE missiles this is a serious hazard. Of course, a well-developed spacefaring civilization should be able to salvage old junk sattelites and conduct clean-up operations of high-traffic orbitals rather easily. It's mostly a problem for us because we have no real space infrastructure; everything we put in space has to be tossed up from the surface at enormous cost.

As for physical crowding ... well, orbitals are quite large. Even just, say, equatorial LEO represents a "land area" equal to a band around the entire equator and then some, and higher orbits like MEO, GEO, and HEO are much larger. I think Lagrange points are rather restricted so there may be some crowding issues there, but if the Jupiter Trojans are any indication the Lunar trojan points should still have plenty of room. Of course, throw up enough stuff and you could still crowding, but you'd need a lot of stuff.

Also, if you start to run out of room around Earth you could try relocating some stuff to the Earth-sun lagrange points.

[18-Till-I-Die]

Of course, throw up enough stuff and you could still crowding, but you'd need a lot of stuff.

Would multiple large space stations count as a "lot"? What i mean is, not up to O'Neil colony sized but large enough for several hundred people to live on them, on a perminent basis. And a few that are larger, but only, maybe, five. They wouldn't all be in close, close orbit like the ISS though. But so if the LEO conprises an area as large as the Earth's equator (give or take, i presume) could you for example have multiple large-scale colonies there without them being elbow to elbow. From what i read Medium Earth Orbit seems absurdly huge, so i take it if they were situated out there there would be no problem.

My main concern is combat, being that i'm not sure how what amounts to having the movie Top Gun happen in Earth Orbit (that's the idea here) would effect them.

[Nyrath]

http://en.wikipedia.org/wiki/Kessler_syndrome

This generally only applies to LEO, higher orbits have more elbow room. The syndrome refers to a chain reaction of collisions, filling LEO with enough tiny shrapnel to make it prohibitively dangerous to lift-off from Earth's surface into orbit.

[Teleros]

My main concern is combat, being that i'm not sure how what amounts to having the movie Top Gun happen in Earth Orbit (that's the idea here) would effect them.

A few ideas, hopefully some of it fairly obvious ...

1. Shrapnel / debris hitting things. Hopefully most stations will have sufficient armour to protect them from the odd bits and pieces, but it's still a danger. The closer space stations are to one another, the more of a risk this poses.

2. Lasers / missiles / bullets that miss their target and continue on to hit something else. Again, the closer space stations are to one another, the more of a risk this poses.

3. Supply runs getting intercepted. Even if most colonies are self-sufficient, damage and the like might make supply runs necessary - and space stations may still need luxury goods, rare metals etc delivered to them anyway.

4. Space stations maintaining orbit (eg thrusters damaged, impacts, sabotage etc). If you can prevent a station from maintaining orbit, you could start pushing it around in space - perhaps as a form of blackmail (surrender or we launch you at the moon) etc. It might be slow, but so long as there's at least some acceleration it'll get moving. LEO stations means it'll probably be easier to shove into the atmosphere to burn up (what about ground installations though?), and so on.

5. Can you fight close by and have a station's guns support you, or do you fight as far from your space station as possible so as to minimise the risk posed to it? Space stations that are closer together could, if armed, even fire upon one another - those with the moon smack bang between them will have to launch either missiles or fighters / drone to attack the other side though.

6. On the training side, might there be regions or particular orbits reserved for training purposes? For example, if all orbital activity is banned from low earth orbit, then you could train relatively safely in an LEO, as any debris would eventually find its way back down to the planet and burn up in the atmosphere. The problem of course would be surface-to-orbital trips, but an alternative would be to situate any training well away from Earth - if you've got that level of infrastructure it's not unreasonable that you can visit the other planets in the solar system. Perhaps Venus is the US Space Navy's base or something . This would also add another element to the story - the distance between Earth and any training bases, both for communications and physically travelling from A to B (made even worse if the Sun's in the way).

7. Finally, the point with the Kessler Syndrome is that it depends both on what the debris is like and what it's hitting. If you can lift heavy masses off Earth cheaply and easily, then ships might simply be too well armoured to be worried about most of the debris. The problem being the massive and / or fast pieces of course...

[Junghalli]

Would multiple large space stations count as a "lot"? What i mean is, not up to O'Neil colony sized but large enough for several hundred people to live on them, on a perminent basis. And a few that are larger, but only, maybe, five.

Think of the space stations as towns and cities scattered along Earth's equator. That should give you a good intuitive sense of how much room we're talking about; it'll take a lot more than five before you start to get serious crowding.

[Nyrath]

1. Shrapnel / debris hitting things. Hopefully most stations will have sufficient armour to protect them from the odd bits and pieces, but it's still a danger.

I get the impression that it is more of a danger than you think.
Examine the image in this article:
http://www.aero.org/capabilities/cords/ ... risks.html
It is a four millimeter crater in the windshield of the Shuttle Orbiter, created by a microscopic fleck of paint (about 0.2 mm diameter). It was traveling at a velocity of between 3 and 6 kilometers per second.

Robinson's First Law of Space Combat states that "An object impacting at 3 km/sec delivers kinetic energy equal to its mass in TNT."

This means that a chunk of debris that is about 30 kilograms would do as much damage as a 16-inch shell fired from the Battleship Iowa.

To protect against that would take lots of armor. And your typical communication satellite has a mass closer to 2500 kilograms.