ESA's Clean Space initiative - Mission e.Deorbit

[catdlr]

ESA's active debris removal mission: e.Deorbit

European Space Agency, ESA

Published on May 31, 2016
ESA's Clean Space initiative is studying an active debris removal mission called e.Deorbit, which will target an ESA-owned derelict satellite in low orbit, capture it, then safely burn it up in a controlled atmospheric reentry. e.Deorbit will be the world's first active debris removal mission, and will provide an opportunity for European industries to showcase their technological capabilities to a global audience.

Source:  http://www.esa.int/Our_Activities/Space_Engineering_Technology/Clean_Space

e.Deorbit project:  http://www.esa.int/Our_Activities/Space_Engineering_Technology/Clean_Space/e.Deorbit

https://www.youtube.com/watch?v=R6yZLbUCU2c?t=001

[Star One]

And here's the direct link.

http://m.esa.int/spaceinvideos/Videos/2016/05/ESA_s_active_debris_removal_mission_e.Deorbit

[MattMason]

I like this. Seems to have several elements of versatility.

If ESA can make a couple or more runs of this on their satellites, the market to bring down old satellites (and therefore free up a space for a new one and save many others from MMOD) is a clear winner. It shouldn't be an ESA-only matter.

I'd like to see a Lockheed-Martin "mini" Jupiter work like this as it has a similar design.

Has anyone heard of any concept that would attempt to capture looser debris using a sieve-like scoop, perhaps? After making several orbits (even changing its altitude to capture items within a certain altitude and angle), it would deorbit itself.

Space is a big place, but I would not want to hear of satellites, manned especially, getting pummeled by the next big problem of space habitation or commercialization.

[Impaler]

The space junk problem has always been one of jurisdiction and profitability as Space law doesn't have oceanic equivalent legal distinctions of derelicts, salvage and navigational hazards.  Solve the legal structure and the tech will fix itself, leave the legal side as it is an any tech will go un-used.

[Lar]

What are the barriers to introducing the equivalent legal distinctions? They seem to conceptually map pretty well...

[Arcas]

I can't tell if it's reusable or consumable. One deorbiter per satellite doesn't seem very feasible, but maybe if they could be launched multiple at a time cheaply, it could work.

[Impaler]

What are the barriers to introducing the equivalent legal distinctions? They seem to conceptually map pretty well...

It should be strait forward to apply the maritime concepts, but guess what country has still not ratified the
UNCLOS if something that basic can't be ratified it's no surprise all of Space has not been dealt with.

Might have something to do with thouse libertarian types that have torpedoed this kind of stuff every time.

[Comga]

I can't tell if it's reusable or consumable. One deorbiter per satellite doesn't seem very feasible, but maybe if they could be launched multiple at a time cheaply, it could work.

The first part seems undeniable: Consuming an entire satellite for each disposal is incredibly expensive.

The second seems insufficient:  Multiple vehicles on a single launch only reduces the cost of launch, not the cost of the satellites.  That will still be tremendously expensive.

Even a third step is doubtful:  If a satellite system could deorbit multiple derelict spacecraft, and there are ways to do this, it would still be too expensive because no one has the incentive to pay for debris removal.  It is much cheaper to wring ones hands and bemoan the debris problem.

Then there are those that think any active, non-cooperative, debris removal is inherently an anti-satellite weapon test.  More benign mission than this have raised that alarm.

edit: A Singapore company is proposing a very similar system.  Best of luck to them.

[a_langwich]

Might have something to do with thouse libertarian types that have torpedoed this kind of stuff every time.

Might it have something to do with those national security types who know what sorts of "derelict" technologies are up there, and don't relish the thought of some Chinese or Russian or eventually North Korean outfit "salvaging" some of their gear?

[Star One]

Might have something to do with thouse libertarian types that have torpedoed this kind of stuff every time.

Might it have something to do with those national security types who know what sorts of "derelict" technologies are up there, and don't relish the thought of some Chinese or Russian or eventually North Korean outfit "salvaging" some of their gear?

But I am sure they'd be equally annoyed if their shiny new satellite that they've just spent a huge amount of money on gets taken out by a random piece of space junk.

[a_langwich]

I can't tell if it's reusable or consumable. One deorbiter per satellite doesn't seem very feasible, but maybe if they could be launched multiple at a time cheaply, it could work.

The first part seems undeniable: Consuming an entire satellite for each disposal is incredibly expensive.

Launching a new rocket with only a token payload is incredibly expensive, too, but you do what you must to prove the system works.

To date, only the shuttle has ever de-orbited a satellite, is that right (not including debris-shower methods)?  I think it's entirely reasonable and desirable ESA, NASA, and Roscosmos fund demonstrations of removal systems for their own previous systems.

You aren't going to proceed with multiple units until you've demonstrated it works at least once.  And even if that particular system isn't the ideal ultimate solution, demonstrating a solution for automated rendezvous and capture of a derelict satellite would still be useful. 

It's like the SpaceX quest for recovering first stages:  maybe parachutes were the right answer, but they were a start.  Maybe trying cold gas thrusters as the control mechanism was doomed, but it was an attempt at the problem.  Maybe their current efforts will be completely eclipsed by better ideas, but now that they've landed first stages, EVERYBODY knows there is at least one solution to the problem.  It has been demonstrated, the challenges and drawbacks and overblown fears have become much clearer.

I don't think even a one de-orbit vehicle per launch is impossible, under certain conditions.

1.  If it fits, including a reasonable amount of maneuvering deltaV,  as a secondary payload to a polar orbit. 

Polar orbits, for anything less than extremely large satellites, typically have a fair amount of margin from the launch vehicle.

2.  If sufficient regulatory/legal/market/idealogical pressure is applied to encourage each polar launch to include this secondary payload.  You might think DOD, NASA and NOAA, as heavy users of this orbital space, would be willing supporters of this.  And I strongly believe Congress would be quite willing to spring some funding for this as well.


The idea is, you design your satellite according to the current guidelines, to de-orbit safely within 25 years or maneuver to a disposal orbit.  The secondary payload is then targeted toward the nearest (in deltaV terms), highest priority item of the same nationality as the main payload.  For example, American polar launches might look for a DMSP satellite "in the area".   I can't imagine much would be possible without electric propulsion.

Each launch then adds a satellite which should contribute none or little to the problem, and removes a large and risky satellite or spent upper stage.

Polar orbits are the most urgent problem.

[Asteroza]

It's the classic commons/Space Guard problem. There's no obvious tax/penalty for indifferent users/bad actors.

The basic problems here being

1. Navigation (which include things like traffic control, NOTAM's, running telescopes/radars to catalog objects)
2. Removal of hazards to navigation (which also ostensibly covers spacecraft safety like minimum equipment standards, and inspection regimes for said safety)(might cover draining the Van Allen belts due to being a rad hazard)
3. Rescue (humans being the priority here, but unmanned is this weird case between minimal recovery to avoid being a hazard and actual salvage)


1 is largely currently covered by military associated organizations like NORAD and the space fence radars, nobody really is ready to start 3 yet, and 2 is requires debris collectors like this ESA design (amongst other designs/ConOps)


Arguably a transnational Space Guard, funded by for example a $/kg to orbit tax on launch providers (cost passed on to payloads), could be considered a fairer approach to dealing with this, if there are some initial rebates for when a stage or sat autonomously and deliberately reenters the atmosphere (good stewardship of the commons). Get contractor providers for the debris collectors open to competitive bidding, and reduced tax burden on reusable tugs that get sent up. Might need a demarcation on which orbits require full collection/removal and which can allow some abandon-in-place (but tanks punctured and the spacecraft bagged with a grapple point and retroreflector, similar to the asteroid capture bag designs), say full removal for stuff below the inner van allen belt or similar.

[Impaler]

I'm wondering if simpler solutions be possible here, you just need to degrade a low Earth orbit a modest amount to send stuff into an eventual death-spiral, the DeltaV is tiny so the smallest drag increase is enough.  Attaching any kind of modest drag producing object to a satellite should suffice, perhaps a bit of electro-static tether which would interact with the Earths magnetic field.  Clearly cheaper then a whole satellite and probably something that a larger satellite (with all the optics, navigation and maneuvering systems being able to be used many times) could dispense out in a manner similar to the net-grab shot.  A company called Tethers Unlimited has designed such a system which they are selling to cube-sats and even larger sats as their do seem to be some regulations about cube-sats needing to de-orbit in a few years.

http://www.tethers.com/TT.html

These kinds of things should be mandatory for new satellites, and their should be debris removal bounties that make it profitable to go up and attach such devices.

In fact propellant-less methods like this are so obviously efficient that I suspect this 'hunter' satellite and the capability to 'dock with uncooperative bodies' is funded more for it's use as an anti-sat weapon (a cleaner kill then the Chinese plan to just shoot things with missiles) then it is an honest attempt to clean up space-junk.

[Impaler]

Might have something to do with thouse libertarian types that have torpedoed this kind of stuff every time.

Might it have something to do with those national security types who know what sorts of "derelict" technologies are up there, and don't relish the thought of some Chinese or Russian or eventually North Korean outfit "salvaging" some of their gear?

No one is returning anything intact to the Earth like in some James Bond movie, this is just burning up on re-entry.  Also you seem to be under the impression that maritime salvage law lets you keep what you salvage, it dose not, the salvor is entitled to a reward of a size determined by the courts.

If nations desired to capture and retrieve each other sats for some national security purpose the lack of salvage law in space would not stop them, nor would it's existence provide cover, as we have seen numerous clandestine attempts by the US to retrieve sunk Russian subs.

[Hanelyp]

Has anyone heard of any concept that would attempt to capture looser debris using a sieve-like scoop, perhaps? After making several orbits (even changing its altitude to capture items within a certain altitude and angle), it would deorbit itself.

Best I have is the idea of a satellite that produces an electrostatic field around itself, effecting a 1/r^3 pseudo-gravity on conductors and dielectrics.  Debris passing nearby would have it's orbit perturbed, in some cases towards an atmosphere intersecting path.  Larger targets might be hit by a low intensity electron beam to increase the force felt.  Timing of when the field is active might allow larger debris being deorbited to boost the electrostatic broom into a higher orbit.

[Lar]

What are the barriers to introducing the equivalent legal distinctions? They seem to conceptually map pretty well...

It should be strait forward to apply the maritime concepts, but guess what country has still not ratified the
UNCLOS if something that basic can't be ratified it's no surprise all of Space has not been dealt with.

Might have something to do with thouse libertarian types that have torpedoed this kind of stuff every time.

Slanging libertarians (or anyone else) isn't helpful. Stay out of political polemics.

Let's also stay out of impugning motives (saying that this is really a way for spy agencies to look at things or defense agencies to take out enemy satellites) as well.

I was tempted to nuke everything that had even a whiff of that. I will if I have to, and not care about the space debris it generates.

[whitelancer64]

Has anyone heard of any concept that would attempt to capture looser debris using a sieve-like scoop, perhaps? After making several orbits (even changing its altitude to capture items within a certain altitude and angle), it would deorbit itself.

Space is a big place, but I would not want to hear of satellites, manned especially, getting pummeled by the next big problem of space habitation or commercialization.

Because space is so BIG, a scoop is impractical. The best way for small debris would be to have a gigantic inflating sphere, something, say on the order of a kilometer or two across, that fills with foam. Small debris impacts and gets embedded in the foam, and its huge cross section means its orbit will naturally decay rapidly due to atmospheric drag.

[MattMason]

Has anyone heard of any concept that would attempt to capture looser debris using a sieve-like scoop, perhaps? After making several orbits (even changing its altitude to capture items within a certain altitude and angle), it would deorbit itself.

Space is a big place, but I would not want to hear of satellites, manned especially, getting pummeled by the next big problem of space habitation or commercialization.

Because space is so BIG, a scoop is impractical. The best way for small debris would be to have a gigantic inflating sphere, something, say on the order of a kilometer or two across, that fills with foam. Small debris impacts and gets embedded in the foam, and its huge cross section means its orbit will naturally decay rapidly due to atmospheric drag.

I seem to recall that the Vectran fabric used for some prototype inflatable modules could make such an expansion. Simply change it to open like a flower. Low weight, very dense, could have that inner foam catching layer.

[MartinW]

If ESA can make a couple or more runs of this on their satellites, the market to bring down old satellites (and therefore free up a space for a new one and save many others from MMOD) is a clear winner. It shouldn't be an ESA-only matter.

It's not ESA-only matter, but there's no market either. ESA, NASA and other space agencies could create market by paying companies to do that, but in the end it's not much different than doing it themselves (would be cheaper, probably more risky, though in case of ESA they want to develop their own technology base, so it's fully understandable that they don't hire Lockheed-Martin or anyone else to develop it and conduct on their own).

Solve the legal structure and the tech will fix itself, leave the legal side as it is an any tech will go un-used.

There were attempts made to make law more restrictive and structured, allowing for precisely what few people here asked, but sadly: they were unsuccessful (in a large part because of USA)

I can't tell if it's reusable or consumable. One deorbiter per satellite doesn't seem very feasible, but maybe if they could be launched multiple at a time cheaply, it could work

The big challenge is a fuel and thrust requirement. For as large and heavy satellite as EnviSat, that has to be deorbited over Pacific (large, uninhabited area) a single, dedicated orbiter is a natural solution. Using one of multiple small deorbiters won't work - even if they'd have the delta-v, they wouldn't have the thrust to deorbit precisely over a designated area.

But I am sure they'd be equally annoyed if their shiny new satellite that they've just spent a huge amount of money on gets taken out by a random piece of space junk.

That's why there's something called space situational awareness and debris avoidance maneuvers.

A company called Tethers Unlimited has designed such a system which they are selling to cube-sats and even larger sats as their do seem to be some regulations about cube-sats needing to de-orbit in a few years. http://www.tethers.com/TT.html

So far most of the tether experiments failed. I dare to say that out of the many, many ideas already presented - we're at the point where it is safe to assume tethers are a wrong one, unless some completely new approach would be done, which this company doesn't have.

I seem to recall that the Vectran fabric used for some prototype inflatable modules could make such an expansion. Simply change it to open like a flower. Low weight, very dense, could have that inner foam catching layer.

Even if it can be done - it's practical only for tiny debries, everything large enough will just fly though, creating even more debris (resulting from the fragmentation of the debris itself and a fragments of the module, though these wouldn't be much of a problem as they'd have a very light weight in relation to volume)

[catdlr]

Clean Space: Netting a satellite

European Space Agency, ESA

Published on Jun 9, 2016
ESA’s proposed e.Deorbit mission plans to demonstrate the retrieval and disposal of a derelict satellite from low-Earth orbit. The mission needs to capture a massive, drifting object left in an uncertain state, which may well be tumbling rapidly. Several capture mechanisms are being studied in parallel – including casting a net.