The not-New Horizons news thread

[K^2]

Maybe we should begin a campaign of crowd sourcing the finance of an ion power drive on a big light weight cage that runs around and picks junk up.

How are you going to do that if the objects aren't being tracked? Keep in mind that debris that presents danger is the kind of stuff that's traveling at several km/s. Even if you manage to pick it up with some sort of radar shortly before impact, you won't have time to maneuver to try and catch it.

Now, you might be able to shoot it down. Modern supercarriers do have weapons designed to track and shoot down re-entering warheads. The relative velocity is in the ballpark. Given the emptiness of space, id est, lack of false targets, you might be able to lock onto something the size of a pebble. Of course, it's going to create even MORE debris, unless you find a powerful enough laser to use in place of an auto-cannon. By this point, we're basically talking about a second station.

[PB666]

How are you going to do that if the objects aren't being tracked? Keep in mind that debris that presents danger is the kind of stuff that's traveling at several km/s. Even if you manage to pick it up with some sort of radar shortly before impact, you won't have time to maneuver to try and catch it.

Now, you might be able to shoot it down. Modern supercarriers do have weapons designed to track and shoot down re-entering warheads. The relative velocity is in the ballpark. Given the emptiness of space, id est, lack of false targets, you might be able to lock onto something the size of a pebble. Of course, it's going to create even MORE debris, unless you find a powerful enough laser to use in place of an auto-cannon. By this point, we're basically talking about a second station.

The radar idea is good, you could have 10 or so satellited getting telemmetry. I was thinking in terms of a garbage truck..

I would propose this, obtain orbit, then using telemetric data find the energetically most close object, capture is and go find the next so on.

There are two things you could do with the junk ---- place in an orbit between the earth and moon in a collection that can at some later point be recycled for use in space ---- take it to an orbit close to final decay orbit, eject it and quickly prograde out. Then the craft could return to ISS have a naut put a new 'cage' and add some more argon gas and send it out again. The idea is to clean the orbital space close to the stations orbit, but not specifically the station itself. For bigger object you might want a pair or trio of ships because hauling a dead satellite would interfere with the drive, do you would couple the drives side by side and tether the satellite in between them.

Shooting down bad idea.

[K^2]

Again, you don't know where that junk is. How are you going to go and pick it up?

[basic.syntax]

Report Finds SLS Cost and Schedule Estimates Tight, but on Track

2015/07/17 13:22 UTC

The Government Accountability Office says NASA is generally doing a good job with cost and schedule estimates for its new heavy lift rocket, the Space Launch System. A report released Thursday said NASA’s SLS paperwork "substantially met" five out of six best practices, while a sixth criteria, credibility, had been partially met. But the 32-page audit also cautioned NASA was running short on schedule margin as it works to have SLS ready for flight by November 2018.

[...snip...]

Potential future SLS payloads include components of the Asteroid Redirect Mission, as well as a robotic mission to Europa.

[PB666]

Again, you don't know where that junk is. How are you going to go and pick it up?

They apparently knew that a piece of junk was coming, got into the Soyuz, and waited for it to pass about 1.5 miles away. So all you need is a radar sensitive enough to detect something once you get within say 5000 meters. Then you lock onto the bugger, cancel the differential velocity and give yourself a few meter per second intercept velocity target the bogey.

I always find it more satisfying to try to do something than to perpetually sit around pondering whether or not it can be done. If someone puts enough effort into it, they could clean up space, you could pay it off by sending a bill to all those countries that put the junk up there, that will stop the Chinese from trying to destroy more of their own satellites. The chances of being able to pick up space junk are much higher than the probability that a warp drive will ever amount to anything, still higher than a VP drive will work. At least we know the basic principles of recognition, targeting, maneuvering and capturing (although I must admit, give the philae landing fiasco, the capturing bit seems a little premature at the moment). In addition for the US it gives them a chance to see exactly what other countries have been throwing up in space, including the technology in dead spy satellites.

- - - Updated - - -

Report Finds SLS Cost and Schedule Estimates Tight, but on Track

Credibility wasn't met? Credibility compared to who? Russians, ESA, contractors?

[K^2]

Ah, so you mean just for the larger debris? Yeah, that could work, then.

[basic.syntax]

SLS:

Credibility wasn't met? Credibility compared to who? Russians, ESA, contractors?

I didn't click through for the details because I was too scared. Now looking at it, I feel justified in not looking, the summary of the details is long-term worrisome.

While an independent NASA office reviewed the estimate developed by the program and as a result the program made some adjustments, officials did not commission the development of a separate independent estimate to compare to the program estimate to identify areas of discrepancy or difference. In addition, the program did not cross-check its estimate using an alternative methodology. The purpose of developing a separate independent estimate and cross-checking the estimate is to test the program's estimate for reasonableness and, ultimately, to validate the estimate.

[Godot]

...If someone puts enough effort into it, they could clean up space, you could pay it off by sending a bill to all those countries that put the junk up there, that will stop the Chinese from trying to destroy more of their own satellites....

How will you get the chinese (or russians, or americans, or indians) to actually pay the bills you send them?

[PB666]

Ah, so you mean just for the larger debris? Yeah, that could work, then.

Well presumably with enough tracking radar you could track sockets for socket wrench and bolts. There is a marginal utility of gain argument at work here. We have to assume that smaller objects have a higher surface area to mass ratio, and therefore more drag, so their orbits will be decaying more quickly. If you then compound the cost in argon to find them and intercept them. Then factor in the fact that a pea size impact is not going to destroy a whole station, you come to the conclusion not to intercept.

But there is an economic argument also, if you track the pea size objects down and collect a few, then send the producing country a bill for say a million dollars, chances are the appearance of new pea size objects will begin to decline over time. So you would probably want to track a few exemplary peas down.

From what I understand the biggest problem right now in LEO is that satellite makers don't want to expend the dozen or so dV to place their satellites into a junk orbit that has been proposed to eliminate the hazard problem. Literally you could create a giant chain link cage in space, and at the end of their operating life the satellites are moved into the cage and attached to the sides or a cable. Large satellites could be attached to the outside of the cage. If parts fall off they are in a safe predictable orbit that is circular and can be tracked down. For non-equitorial satellites you have a bit of a problem, to get them to one place you would have to expend alot of dV to change the inclination.

- - - Updated - - -

How will you get the chinese (or russians, or americans, or indians) to actually pay the bills you send them?

You present the bill at some international space conference and embarrass them. Seriously what the Chinese did was dumb and irresponsible, given that a little public shaming is good for their souls.

[K^2]

Well presumably with enough tracking radar you could track sockets for socket wrench and bolts.

Within proximity of the station, sure. But again, things that move fast enough to present danger need to be tracked long before they are in proximity. Hence the softball size limit on what we can track. Things larger than softball, for the most part, we know where they are all the time. But even if we know about them in advance, not much we can do about it. Smaller things we could do something about, but we can't track them.

[PB666]

Within proximity of the station, sure. But again, things that move fast enough to present danger need to be tracked long before they are in proximity. Hence the softball size limit on what we can track. Things larger than softball, for the most part, we know where they are all the time. But even if we know about them in advance, not much we can do about it. Smaller things we could do something about, but we can't track them.

I think that would depend on proximity, the closer you are to a radar site, the bigger its profile will be to the radar. It we know where they are then we can intercept them. Obviosly the ISS can't intercept them. But a smaller more agile probe could. I see this as a situation that once you start removing the superbaseball size objects, then things that are smaller will be more readily tracked and followed.

So for example. If we have x-radars in space now monitoring positions. If we place 8x in space we will be able to see things half the diamter of a baseball. If we place 64x in space we can monitor things 1/4th the diameter of baseballs. I suspect most of the monitoring is being done from Earth, so simply closing the gap between Earth and space will increase the resolution of the monitoring.

[Camacha]

So for example. If we have x-radars in space now monitoring positions. If we place 8x in space we will be able to see things half the diamter of a baseball. If we place 64x in space we can monitor things 1/4th the diameter of baseballs. I suspect most of the monitoring is being done from Earth, so simply closing the gap between Earth and space will increase the resolution of the monitoring.

Are you flying by the seat of your pants or are you actually calculating or guesstimating your things based on something?

[PB666]

Are you flying by the seat of your pants or are you actually calculating or guesstimating your things based on something?

Its a reasonable guess, I of beam bounce is k*A/d^4, something half the size will be recognized at 70% of the distance, but contact only occurs 50% of the time. IOW it will occupy the beam 35% of the time and have 1/2 the contacts. Smaller objects orbit degrade faster and need more monitoring, and a lower reflection means orbits with higher periapsis may not be monitored at all. So where between 5 and 10 times as many radar would be need to improve collective resolution by 2.

The caveot is that the radar must be in space, since on the ground one would have to greatly scale up I as a square inverse square function of diameter.

[kiwi1960]

How will you get the chinese (or russians, or americans, or indians) to actually pay the bills you send them?

Sadly, under international law, if you clean up the space around the earth, you will start a war.

Any space object launched, working or not, is protected by international law and even touching it would be classed as an act of war.

The only way space will be cleaned up is if all those nations that created the mess sign a waiver... but I cannot see the US doing that, or China, if there is a chance that their secrets would be on sold to a third party....especially the spy satellites...

[WinkAllKerb'']

silly question: how old are the "inter"national"" law ? ... hum oki nevermind ...

[WinkAllKerb'']

nati: latin : being born somewhere ... is this somewhere earth or a country within "fictive" coarsely drawed frontier ... who still care thoose not even middle age inter "nati" law concept ... cavern people ? seriously ... wake up a litl' and grow plox ...

hum may be people that like to send other fight in there name while sitting in a chair still like this old concept ; ) but hey time to time things end you know ; )

(bumped because i was expecting someone to answer faster ...)

Edited July 19, 2015 by WinkAllKerb''

[PB666]

Sadly, under international law, if you clean up the space around the earth, you will start a war.

Any space object launched, working or not, is protected by international law and even touching it would be classed as an act of war.

The only way space will be cleaned up is if all those nations that created the mess sign a waiver... but I cannot see the US doing that, or China, if there is a chance that their secrets would be on sold to a third party....especially the spy satellites...

Thats my missing lug-nut no its my wrench socket, time to start a war. If we can only track baseball size objects, and there are alot of smaller objects out there, how do they know that the missing bolt or the loosened piece of insulation is theres scrap. Sounds like another misguided regulation.