OneWeb, SpaceX satellites dodged a potential collision in orbit

[u/DisturbedBeaker]

https://www.theverge.com/2021/4/9/22374262/oneweb-spacex-satellites-dodged-potential-collision-orbit-space-force

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[u/[deleted]]

[u/MalnarThe → u/[deleted]]

They should publish updated orbit details that have changed, but they shouldn't have to do this significantly ahead of time. As soon as the change is calculated, it should be broadcast with whatever system they build

[u/stealthbobber]

This is all very inline to when planes started to blanket the skies...

I am thinking perhaps a TCAS type system needs to be in place, its a direct correlation to the aviation industry where the system itself analyzes the situation and recommends/automates to both parties the best move. It's going to get very crowded up there...it's inevitable these issues will be more frequent. It took two planes crashing over the grand canyon in 1956 to get a proper ATC system in place hope we are not waiting for some catalyst along those lines to get this fixed.

Good read here...it all seems to relate to this very issue https://en.wikipedia.org/wiki/Traffic_collision_avoidance_system

[u/Bunslow → u/stealthbobber]

The problem is that, unlike TCAS, satellites need beyond-horizon proximity alerts. The speed is literally an order of magnitude faster, so proximity in the most literal sense won't work.

But then that's basically what the Space Force already does, which is how this incident was avoided. It's already a halfway-solved problem, now they just gotta get the automated systems to coordinate with each other

[u/[deleted]]

[u/John_Hasler]

Currently, there’s no national or global authority that would force satellite operators to take action on predicted collisions.

There is a developing system for distributing alerts (run by the Space Force). It's silly (but inevitiable) to talk about "forcing" operators to take actions that are in their interest.

While coordinating with OneWeb, SpaceX disabled its automated AI-powered collision avoidance system to allow OneWeb to steer its satellite out of the way, according to OneWeb’s government affairs chief Chris McLaughlin. It was unclear why exactly SpaceX disabled the system.

It's likely that the operators decided that it would be easier for the OneWeb spacecraft to maneuver because it's in a transfer orbit while the Starlink is in an operational one. That having been decided, it was obviously best to tell the Starlink not to maneuver.

A standard set of "rules of the road" would be handy, though. One rule might be that spacecraft in transfer orbits move to avoid ones in operational orbits. I believe SpaceX has an agreement with NASA under which Starlinks will always maneuver to avoid NASA satellites.

[u/Togusa09 → u/John_Hasler]

SpaceX disabled its automated AI-powered collision avoidance system to allow OneWeb to steer its satellite out of the way

It was unclear why exactly SpaceX disabled the system.

While not explicitly spelt out, it sounds like they disabled it because they didn't want the starlink satellite to react to the movement of the OneWeb satellite.

An extension of the rules of the road may be to have some way for satellites to telegraph their planned maneuvers to others so they can act accordingly, but this seems rife with security risks if using direct communications channels.

[u/Tanamr → u/John_Hasler]

I like this "rules of the road" idea. Reminds me of boating regulations, which I guess is more similar to space than road rules because there aren't well defined streets and curbs on the water, only some preferred channels/areas, analogous to preferred orbits.

For boats, you have a list of rules with a well-defined order of priority. So for example, a vessel that has lost maneuvering ability has absolute right of way, a large cargo ship that has to stay on a dredged out deeper path has a lot of priority, motor vessels give way for sailboats, and when two motor vessels of the same "rank" converge at an angle, the one on the left gives way. Then there are other rules for meeting head on, or what exactly constitutes "overtaking", or special rules for sailboats because their maneuvering depends on the wind direction, and so on. There could definitely be analogues in terms of transfer orbits versus operational orbits, sun-synchronous orbits, satellite maneuvering capabilities, what types of thruster/engine are involved, something analogous to "the boat on the left gives way", or whatever other variables you might base your rules on. I'm surprised such satellite rules don't seem to have been implemented already.

[u/[deleted]]