OneWeb, SpaceX satellites dodged a potential collision in orbit

SpaceX has an automated system, that can be overridden to coordinate with others, which is exactly what they did in this case. I don't see why that's bad? If they refused to override and coordinate maneuvers, that's one thing, but they didn't.

Having a system that can maneuver itself in the absence of outside intervention seems like a good thing when time to respond is measured in milliseconds under certain circumstances.

This seems like collision avoidance systems in cars, easily overridden but functioning when the driver isn't paying attention.

Yes, something like this should exist, but its very tricky to do as this is a global resource.

There are few enough sats that it often still works as 'I know the guy who does operations at XY company or government and how to call them'.

Unfortunately there is not even a global index of all sats with an easy way to reach the operator. Such a list exists but the phone numbers are often simply the public number of the space agency of that country. And getting from the China Space Agency to the person that can actually move the Sat it can be tricky.

Not to mention that there are dead objects that simply can not be moved.

The state of the art is moving forward slowly, both in monitoring and avoidance.

It turns out OneWeb as lying to to the press. https://twitter.com/joroulette/status/1384694830643679239

Starlink satellites are a bit bigger than that from what I can gather on google at least.

> came "close" to colliding, when a half second later they would be 8000 meters apart.

So is a bullet if it goes through you. Space is big but the orbits these satellites operate in aren't as big as space itself.

Why does it matter if it's hard to believe anyway, they gave a figure of 1.3%, which is pretty low anyway, and they didn't do it on the back of a napkin.

"Space Force’s urgent alerts sent OneWeb engineers scrambling to email SpaceX’s Starlink team to coordinate maneuvers that would put the two satellites at safer distances from one another."

This is exactly how it should work though.

I once met with Iridium [1] engineers not long after the collision of one of their satellites with a Russian weather satellite [2] in 2009. The meeting was for another purpose entirely, but since the collision was fresh news, it naturally came up in conversation. The Iridium folk told me that they would receive warnings from NORAD of imminent collisions, defined as two satellites coming with 500m. They were receiving warnings to the tune of 10 or 12 a day, so many that they basically started ignoring them.

[1] https://www.iridium.com/ [2] https://en.wikipedia.org/wiki/2009_satellite_collision

Yeah that's a good thread.

If a Starlink satellite fails the drag alone will deorbit it within five years or so. (this actually happens, they used to have 5% failure rate)

Of course a collision event is chaotic. The debris is catapulted in all directions, changing the orbit. But because of how orbital mechanics works their new orbit will still pass through their old orbit, so every piece of debris will deorbit eventually (unless it impacts something else first).

Being so low reduces the risk considerably, and even with a couple thousand satellites more we are talking about mostly empty space.

Not all of them.

Practically all space debris collisions in LEO will be hypervelocity collisions (the kinetic energy of the impact is greater than the explosive energy released by the same mass of TNT)

When collision happens in LEO, some fragments gain more velocity than the colliding satellites. They may end up in higher orbits where they can stay for a very long time.

Just to make sure you realize. SpaceX was not at fault here at all. They went out of their way to help OneWeb even though their satellites normally maneuver automatically.