What happens to all that debris?

cthia wrote:Adding a bit of broth to the stew . . .

Uncompromising Honor wrote:She didn’t take her eyes off of her own panel, though. The debris field traveling through the Hypatia System seemed tiny and forlorn as the last memorial to the two thousand or so men and women who’d given their lives so that six million might live, but its components were moving across the system at better than 15,000 KPS and spreading laterally at over ninety KPS. That meant it was actually over a million kilometers in diameter—a hemisphere with a volume of almost eleven cubic lightseconds. Despite its spread, the debris was dense enough to present a genuine hazard to navigation, and Asteria’s particle screens weren’t as powerful as those of larger vessels. The good news, if it wasn’t obscene to call anything “good” in the wake of such carnage, was that her shuttle was traveling with the debris. It had been for several hours, now—many of the other rescue craft had exhausted their endurance and been forced to break off after conducting SAR over such a vast space on top of their grueling efforts to evacuate the orbital habitats—but at least that meant the relative velocities weren’t as high as they might have been.

I'm wondering what kind of difficulty Debnam and Paulette might experience after successful recovery of the life pods, then needing to safely get OUT of the debris field.

ThinksMarkedly wrote:The debris field is roughly stationary compared to the rescue craft moving inside it. That's what the "good news" portion of the paragraph you pasted means. The biggest difficulty is actually negating that 0.05c and getting back to a safe harbour.

I imagine it's a navigational hazard for multiple reasons. For everyone not moving in lockstep with it, it's a large field that contains all sorts of pieces, many of which sufficiently big and/or in sufficient quantity to overload the particle screens, and moving at high speed compared to the primary. For anyone who matches velocities, the small pieces wouldn't be an issue, but the big ones still would.

I understand the "good news" part of it. My pubescent days on a large skating rink applies. Trying to get out of the melee without incident is the trick. Anyway, it won't remain that way once the shuttle claims its prize and needs to get back to base. Plus, she's running a little low on fuel, probably not dangerously low. But the debris field is pretty big. It has spread a million kilometers wide thus far.

cthia wrote:I understand the "good news" part of it. My pubescent days on a large skating rink applies. Trying to get out of the melee without incident is the trick. Anyway, it won't remain that way once the shuttle claims its prize and needs to get back to base. Plus, she's running a little low on fuel, probably not dangerously low. But the debris field is pretty big. It has spread a million kilometers wide thus far.

How bit a problem it become for their return depends entirely on how fast they have to return. If they've got a medical emergency or are running low on life support and need to return to base ASAP then yes they'd be accelerating hard through parts of the field and would quickly build up a dangerous relative velocity.

But we don't know whether they have any such time limit.

If they can take their time they can keep their speed, relative to the field, low and creep their way clear before using any major acceleration. That shouldn't be any more risky than what they're already doing traversing slowly through the field looking for life-pods or other survivors. Once they're clear there's still some chance of finding an piece of debris trailing anomalously far behind the field - but most of the risk would be behind them (or possibly beside them; depending on which edge of the field they worked they way out of )

Jonathan_S wrote:

cthia wrote:I understand the "good news" part of it. My pubescent days on a large skating rink applies. Trying to get out of the melee without incident is the trick. Anyway, it won't remain that way once the shuttle claims its prize and needs to get back to base. Plus, she's running a little low on fuel, probably not dangerously low. But the debris field is pretty big. It has spread a million kilometers wide thus far.

How bit a problem it become for their return depends entirely on how fast they have to return. If they've got a medical emergency or are running low on life support and need to return to base ASAP then yes they'd be accelerating hard through parts of the field and would quickly build up a dangerous relative velocity.

But we don't know whether they have any such time limit.

If they can take their time they can keep their speed, relative to the field, low and creep their way clear before using any major acceleration. That shouldn't be any more risky than what they're already doing traversing slowly through the field looking for life-pods or other survivors. Once they're clear there's still some chance of finding an piece of debris trailing anomalously far behind the field - but most of the risk would be behind them (or possibly beside them; depending on which edge of the field they worked they way out of )

I did feel they were a bit rushed to get the injured parties back. Admiral Kotouč's injuries were quite extensive, and severe. His spine was severed in three places if I'm not mistaken, and he had no legs. Apparently it isn't common knowledge whether a crew member responds to regen. I would imagine she felt rather anxious about getting the Admiral to a doctor, asap, regardless.

He had been tranqed to the Manticoran allowed limit. Apparently, too, you can't commit hara-kiri with your meds and float away into oblivion while you're. . .floating away into oblivion. Not on the RMN's dime. Although during the first read through, I wondered whether the pod can simply be opened to vacuum? Probably not too.

Anyway, the pods powered systems had long been kaput, although textev says the endurance of the skinsuit is much higher. The two rescuers also had not been successful at finding people alive in the pods, which would naturally make them anxious not to lose these two when they found them alive. Especially since one of them was the Admiral.

And do note the debris field was such a hazard she kept her eyes on her panels. Plus, the two of them had been "driving" far longer than regulation allowed and because of that, the chance of an error caused by exhaustion was high.

Jonathan_S wrote:If they can take their time they can keep their speed, relative to the field, low and creep their way clear before using any major acceleration. That shouldn't be any more risky than what they're already doing traversing slowly through the field looking for life-pods or other survivors. Once they're clear there's still some chance of finding an piece of debris trailing anomalously far behind the field - but most of the risk would be behind them (or possibly beside them; depending on which edge of the field they worked they way out of )

Since the explosions were at a considerable distance from the planet and the return port for the shuttle; there should be a course that slants through the debris movement, keeping the wedge in position to protect from the debris. This should be much faster than a route parallel to that movement. The limiting speed is determined by whether a object that inside the area of the throat can be overtaken by the hull (provided that it is big enough to strain the particle deflector).

tlb wrote:

Jonathan_S wrote:If they can take their time they can keep their speed, relative to the field, low and creep their way clear before using any major acceleration. That shouldn't be any more risky than what they're already doing traversing slowly through the field looking for life-pods or other survivors. Once they're clear there's still some chance of finding an piece of debris trailing anomalously far behind the field - but most of the risk would be behind them (or possibly beside them; depending on which edge of the field they worked they way out of )

Since the explosions were at a considerable distance from the planet and the return port for the shuttle; there should be a course that slants through the debris movement, keeping the wedge in position to protect from the debris. This should be much faster than a route parallel to that movement. The limiting speed is determined by whether a object that inside the area of the throat can be overtaken by the hull (provided that it is big enough to strain the particle deflector).

Well, I was wondering why Paulette couldn't simply roll ship, treating any incoming debris as missiles. But then, further reading talks about the "hook" or wench used to grab the pods, which implies the shuttle has to be oriented a certain way to make the connection?

THEN, can't she just roll ship while exiting? Keeping in mind that all of the debris, though traveling together, isn't traveling at the same speed. I suppose a shuttle has no sidewalls.

cthia wrote:can't she just roll ship while exiting? Keeping in mind that all of the debris, though traveling together, isn't traveling at the same speed. I suppose a shuttle has no sidewalls.

If all the explosions happened at about the same time and place, then the debris in any particular region are all traveling at roughly the same speed (distance from explosion divided by time from the explosion). There is no sidewall, but you can interpose the wedge. However there is a limiting velocity depending on the angle between the shuttle and debris directions and the debris velocity; if you go too fast the debris that clears the wedge can be overtaken by the shuttle.

tlb wrote:

cthia wrote:can't she just roll ship while exiting? Keeping in mind that all of the debris, though traveling together, isn't traveling at the same speed. I suppose a shuttle has no sidewalls.

If all the explosions happened at about the same time and place, then the debris in any particular region are all traveling at roughly the same speed (distance from explosion divided by time from the explosion). There is no sidewall, but you can interpose the wedge. However there is a limiting velocity depending on the angle between the shuttle and debris directions and the debris velocity; if you go too fast the debris that clears the wedge can be overtaken by the shuttle.

Well, I'm thinking some of the debris will undoubtedly be ejected at varying forces and intervals along the same vector, bringing up the rear. The fact that Paulette has to keep her eye on her panels supports that. If the shuttle is traveling at a friendly pace equal to everything else traveling at a friendly pace, then nothing will be tailgating, thus, no need for her to keep her eyes on her panels. In fact, I suspect there is a fair bit of pinball physics going on in a debris field. Or more aptly, small windows into the Big Bang Theory. Or, even the physics of a much smaller fission reactor, with the debris standing in for atoms.

cthia wrote:Well, I'm thinking some of the debris will undoubtedly be ejected at varying forces and intervals along the same vector, bringing up the rear. The fact that Paulette has to keep her eye on her panels supports that. If the shuttle is traveling at a friendly pace equal to everything else traveling at a friendly pace, then nothing will be tailgating, thus, no need for her to keep her eyes on her panels. In fact, I suspect there is a fair bit of pinball physics going on in a debris field. Or more aptly, small windows into the Big Bang Theory. Or, even the physics of a much smaller fission reactor, with the debris standing in for atoms.

The explosions imparted velocities with arbitrary amplitude and direction to the various pieces of debris. Subsequent collisions between them further made a mess of things. That means inside the debris field, if you subtract the base velocity of the ships before the explosions, each piece of debris is moving in random vectors.

And this base velocity is what the SAR ships must match. That means that from the point of view of the ship while conducting the search, the debris is coming from all directions. There's no preferred direction to interpose the wedge at: debris can still come from the sides, throat, or kilt. Worse, there is a preferred direction when the ship is moving and that's directly down the throat, which is the widest part of the wedge.

And to make things even more complicated, you don't want to interpose your wedge. That would mean you're not rescuing anybody, just vacuuming debris. The SAR birds' sensors are probably not good enough to scan through the wedge and probably not nimble enough to rotate to take the wedge away from anything interesting it did find. In fact, it's entirely possible the wedges were down at this point and the SAR ships were moving only on reaction thrusters. The wedges might do more harm than good inside the debris field.

ThinksMarkedly wrote:The explosions imparted velocities with arbitrary amplitude and direction to the various pieces of debris. Subsequent collisions between them further made a mess of things. That means inside the debris field, if you subtract the base velocity of the ships before the explosions, each piece of debris is moving in random vectors.

And this base velocity is what the SAR ships must match. That means that from the point of view of the ship while conducting the search, the debris is coming from all directions. There's no preferred direction to interpose the wedge at: debris can still come from the sides, throat, or kilt. Worse, there is a preferred direction when the ship is moving and that's directly down the throat, which is the widest part of the wedge.

And to make things even more complicated, you don't want to interpose your wedge. That would mean you're not rescuing anybody, just vacuuming debris. The SAR birds' sensors are probably not good enough to scan through the wedge and probably not nimble enough to rotate to take the wedge away from anything interesting it did find. In fact, it's entirely possible the wedges were down at this point and the SAR ships were moving only on reaction thrusters. The wedges might do more harm than good inside the debris field.

It was my understanding that we were discussing the trip home, after the SAR work was done. At the point where this shuttle found its final pod, the direction and speed of the debris field would not have much local deviation; since this is hours after the battle was over. in the return home you definitely want to interpose the wedge.

tlb wrote:It was my understanding that we were discussing the trip home, after the SAR work was done. At the point where this shuttle found its final pod, the direction and speed of the debris field would not have much local deviation; since this is hours after the battle was over. in the return home you definitely want to interpose the wedge.

I don't agree. Even if this is the last shuttle in SAR, there may be other reasons to come back. Vacuuming the debris field unnecessarily does not sound like good practice.

What I do expect is that the first SAR shuttles created a tunnel of safe volume through which using the wedge is acceptable. Incoming and outgoing shuttles would stick to it when going to their search zones and thereby avoiding areas of increased hazard.

Either way, that doesn't solve the problem of debris coming from all directions. The wedges help with up and down, plus a great deal of sideways because they're very wide. But they can't stop all sideways motion. And they especially don't help with the direction of motion and that's exactly where most of the debris is going to be coming from.