Stuff in Space

[LordFerret]

Look at the debris track from Iridium 33. (top left of screen, under 'Groups')

[Camacha]

Kessler Syndrome is overrated.

It certainly is not overrated, it currently is a matter of time. This is exactly how air and sea pollution started. 'Enough sea/air, this will never be a problem'. The same goes for air traffic control, so much air and so little aircraft, until they started colliding more and more. Act now, and reduce the hurting later.

[Hcube]

The real question why you think this would be perfectly predictable It is a phenomena that has been unseen and untested, just predicted. Of course it is a matter of approximations, since the mechanics are not fully understood and verified. Even extensively studied and tested systems have a fair degree of deviation when it comes to predictions.

Well, if you know the size and the orbits of most objects in space, and have a fair estimation of what orbits the small-and-difficult-to-track debris have, wich is the case, calculating the probability of having two of them collide should be doable... Then you could establish different scenarios depending on how much smaller debris is released for each collision. It sounds doable to me... and yet no one really knows when that could happen.

Do NASA, ESA, ROSCOSMOS or any other space agencies actually run models and simulations for this ? They could have a model like stuffinspace and adding newly discovered debris over time, thus updating the model and upgrading the precision of the probabilities...

I know such a thing is done for the ISS but what about the kessler effect ?

[lajoswinkler]

I'm pretty sure this map is nowhere near the actual number of detectable objects. I mean come on, there's way more stuff up there.

[smjjames]

It certainly is not overrated, it currently is a matter of time. This is exactly how air and sea pollution started. 'Enough sea/air, this will never be a problem'. The same goes for air traffic control, so much air and so little aircraft, until they started colliding more and more. Act now, and reduce the hurting later.

Yeah, even if it's not enough to trigger a kessler cascade (or perhaps just a low probability), debris are already a concern right now since the ISS has had to dodge debris a bunch of times already.

[KerbMav]

Act now, and reduce the hurting later.

I welcome you to planet Earth, my intergalactic friend! What is the name of your species?

[adsii1970]

Currently there are about 2465 artificial satellites orbiting the Earth. Imagine doing that in KSP.

Actually, I don't want to... the lag on my system is bad enough with a space station, five satellites, and three shuttles in orbit. Makes for some interesting missions, however. Now, having mapped the surface using SCANSAT and the stock system, I only need to keep two in orbit. Thinking about refitting the satellites in orbit and sending them out to other targets...

[LordFerret]

I'm pretty sure this map is nowhere near the actual number of detectable objects. I mean come on, there's way more stuff up there.

I agree. Too bad all the Earth orbiting rocks aren't shown as well.

[Bill Phil]

It certainly is not overrated, it currently is a matter of time. This is exactly how air and sea pollution started. 'Enough sea/air, this will never be a problem'. The same goes for air traffic control, so much air and so little aircraft, until they started colliding more and more. Act now, and reduce the hurting later.

It is not as problematic as everyone's saying.

Space is not air, it's not sea, and it is certainly big enough that there won't be a major problem for generations.

It even solves itself. The debris eventually becomes molecule sized, and thus is less of a threat.

[smjjames]

It is not as problematic as everyone's saying.

Space is not air, it's not sea, and it is certainly big enough that there won't be a major problem for generations.

It even solves itself. The debris eventually becomes molecule sized, and thus is less of a threat.

'eventually' is an EXREMELY long time though.

Sure it might not be as problematic as everybody is saying, but it's problematic enough to worry about debris colliding with the ISS.

[Bill Phil]

'eventually' is an EXREMELY long time though.

Sure it might not be as problematic as everybody is saying, but it's problematic enough to worry about debris colliding with the ISS.

That's not worry about Kessler Syndrome, it's worry about losing an asset that cost over a hundred billion dollars.

Not to mention that a Kessler Cascade would take years, if not decades, to start causing minor issues. These aren't dominoes here.

[Camacha]

Space is not air, it's not sea, and it is certainly big enough that there won't be a major problem for generations.

That is exactly what they said about air and sea. It is outright stupid to think space is any different than the areas where we made mistakes before. Also, cascading trouble is much less likely in air and sea.

It even solves itself. The debris eventually becomes molecule sized, and thus is less of a threat.

A huge problem is that before it becomes molecular sized, it will go through an extensive phase of small to medium size chunks that are extremely dangerous, harmful and plentiful. Even if it is molecular sized, there will still be larger chunks being highly dangerous.

Downplaying Kessler's Syndrome will not do. It might take a while to get there, but if it happens we will be hurting for a rather long time. The time to start reducing the problem is now.

Not to mention that a Kessler Cascade would take years, if not decades, to start causing minor issues. These aren't dominoes here.

That would possibly be even more painful, slowly watching the unstoppable train wreck unfold. Earth bound before we ever really got to space.

[LordFerret]

The way I see it, it's already an issue. We've got the ISS and other vessels dodging debris. We've numerous incidents of the Shuttle(s) alone with 'paint chip' and other small debris impacts on windows and elsewhere. Between Iridium 33's collision and the other various satellites which have exploded (2 or 3 that I can think of), there's a lot of debris flying around up there ... not to mention all the stuff/rocks that were there to begin with.

[smjjames]

LordFerret is correct here, it doesn't need to be actively kessler cascading to be a problem, it's ALREADY a problem right now. Which is why there was such an outcry over China deciding to explode a sattelite, even if it was a defunct one. One large piece of debris is easier to track than 4,000 smaller ones.

[pincushionman]

The real problem is there isn't yet a good way to eliminate the mess, as big or little as it is, that we have there already. The dV requirements to de-orbit an object are not trivial even for a functioning satellite. Modern techniques like graveyard orbits and release of un-spent fuel only reduce the chances of a catastrophe a little - the stuff is still up there.

And malfuctioning satellites are a whole 'nother kettle of fish - they're stuck where they are.

[J.Random]

debris are already a concern right now since the ISS has had to dodge debris a bunch of times already.

We've got the ISS and other vessels dodging debris.

You may need to read on when exactly DAM is executed.

[LordFerret]

You may need to read on when exactly DAM is executed.

A PDAM was executed the day before the ISS had its thruster mishap (I even posted about it here in the forums). Nobody seems to have caught that though, everyone was too wrapped up in the thruster misfire event.

Edit:

Here's the link (I think it's the same I posted)...

http://www.nasaspaceflight.com/2015/06/iss-dodges-minotaur-debris-pdam/

Edited July 8, 2015 by LordFerret

[Albert VDS]

Not at all. It means that once there is a large number of satellites (large being many many times more than the current number of satellites) around Earth the likelihood of a "Kessler Syndrome Event" will be high enough that it's a guarantee.

The current satellite density is pretty low. Many thousands of satellites within a very large amount of space.

Kessler Syndrome is overrated.

Yes there are collisions, but they're not very common.

Sure there is a threshold where it's a guarantee that a Kessler cascade even will happen, but there's also uncontrollable satellites and debris big enough to increase the odds.

For example Envisat, which is a non functional satellite with a weight of 8,211 kg.

This is a problem and should be dealt with even if it turns out to only occur after a few generations.

The easiest time to solve it is now, not in 20 years.

Edited July 8, 2015 by Albert VDS

[J.Random]

A PDAM was executed the day before the ISS had its thruster mishap (I even posted about it here in the forums). Nobody seems to have caught that though, everyone was too wrapped up in the thruster misfire event.

Edit:

Here's the link (I think it's the same I posted)...

http://www.nasaspaceflight.com/2015/06/iss-dodges-minotaur-debris-pdam/

Not my point. You say, ISS has to dodge debris all the time. I say, read on actual PDAM requirements. It's not like they dodge a bullet every time they move ISS. PDAM is executed when anything is predicted to come through the ISS security envelope (I'll leave it to you to google the "pizza box" dimensions) and has a 1:100000 chance of hitting ISS (some sources say that yellow danger level starts at 1:20000). It's not "OMG CLOUD OF DEBRIS WILL HIT ISS IN 90 MIN! WARP ONE MR SULU!" More like "Huh. This crap may get as close as 25km to ISS. Let's move it just to be sure."

Debris is a problem, sure. It's getting more of a problem as we put more things in space. But it's getting blown out of proportion by graphical representations like the one linked in the OP. Measures have been taken already, with the requirement to deorbit satellites or put them into graveyard orbits.

Space is HUGE.

[Albert VDS]

Debris is a problem, sure. It's getting more of a problem as we put more things in space. But it's getting blown out of proportion by graphical representations like the one linked in the OP. Measures have been taken already, with the requirement to deorbit satellites or put them into graveyard orbits.

Space is HUGE.

That is true, but there's the problem of objects we can't control anymore and can stay in space for 100+ years.

[Camacha]

Debris is a problem, sure. It's getting more of a problem as we put more things in space. But it's getting blown out of proportion by graphical representations like the one linked in the OP.

Space is HUGE.

Why do people keep insisting things are blown out of proportion? If you would show how it actually looks, you would see nothing, because satellites are a lot smaller than the pixels of your screen. You cannot show this phenomena without inflating the size of the satellites to a detectable level.

Now that we got rid of that misunderstanding, we can discuss how it is already a problem to be taken into account and will only become bigger. Space is huge, just like the ocean and the sky are huge. We need to act early and we need to act effectively. That way we can mitigate the problem before it develops into a huge issue.

Not my point. You say, ISS has to dodge debris all the time. I say, read on actual PDAM requirements. It's not like they dodge a bullet every time they move ISS. PDAM is executed when anything is predicted to come through the ISS security envelope (I'll leave it to you to google the "pizza box" dimensions) and has a 1:100000 chance of hitting ISS (some sources say that yellow danger level starts at 1:20000). It's not "OMG CLOUD OF DEBRIS WILL HIT ISS IN 90 MIN! WARP ONE MR SULU!" More like "Huh. This crap may get as close as 25km to ISS. Let's move it just to be sure."

You are missing the point. The point is that the ISS already has to move out of the way of debris. Whether that is 25 kilomtres of 5 metres does not matter at all. The fact is that NASA feels it is too close to forego an intervention is what counts.

No one is purporting NASA is moving the ISS out of the way because it will get hit Gravity the movie style otherwise. That is just silly.

I welcome you to planet Earth, my intergalactic friend! What is the name of your species?

Greetings from the Homo Preventus You have a very pretty planet, though it seems to be tarnished by strange substances in its atmosphere and oceans. Do you require assistance of some sort?

Edited July 8, 2015 by Camacha

[J.Random]

Guys. This site shows some 2500 objects and it's scary? It's actually close to 19000 man-made objects (2009 NASA report). If you include natural objects (which always were there and somehow didn't cause Kessler cascade), it's estimated as up to 300000 objects larger than 1cm (same report). Now, what would be a proper representation? Spatial density graphs and cumulative flux maps. They can also be scary if you look at the graphs themselves (OMG IT HAS DOUBLED IN THE LAST 10 YEARS), but then you look at numbers and they're all like 10^-8 objects per km^3, or 10^-6 objects per m^2 (yearly accumulated flux).

ISS performed 5 PDAMs in 2014, 0 (zero) in 2013, 3 in 2012. That's the amount of tracked objects which passed through the 25km-wide "pizza box" and had a chance of hitting ISS higher than 1:100000.

Most of the above was taken from http://orbitaldebris.jsc.nasa.gov/. At least it has numbers, not just pictures of extremely crowded near-Earth space.

[Camacha]

(which always were there and somehow didn't cause Kessler cascade)

No one ever claimed natural objects are not also a thread to space flight.

[YNM]

Why are we put a fire on kessler syndrome, based on thoughts and not some observations and calculations ?

My own thinking : probably we can somewhat model whether is it a threat already or not by trying to think it akin of ideal gasses. Knowing the density (mass density as well) and the mean square velocity we could calculate pressure... Which is force times area (substitute a typical cross-section, or a specific object), and force is change of momentum each instance of time. Momentum is (again) related to speed and mass, so probably we can model a typical "projectile" out there and knowing when the change in momentum more or less equals a single projectile knocking the object. Is it possible ?

[Camacha]

This seems to be relevant.

- - - Updated - - -

This seems to be relevant.