[prepend]

The language in this article seems to be making more of this than it is…

For example, “forced to swerve” is very different from “adjust course to avoid collision.”

There are 4,000 starlink satellites with an eventual plan for 12-40k [0] so it seems reasonable to need to maneuver to avoid crashes. Satellites weren’t “forced to swerve” 25,000 times, they just changed their course.

It would be like me describing my morning commute as “swerving 600 times” because I had to adjust around every object in my way during my 14 mile drive.

There’s traffic in space.

[0] https://en.wikipedia.org/wiki/Starlink

[andy_ppp]

Yes I was going say, the framing seems weird. Isn’t it great the didn’t hit anything? Also that we know this accurately where all the debris is and can avoid this issues is incredible engineering.

[mortehu]

If the were no lanes and everyone was just driving in a huge field with no brakes, your analogy would make more sense. When there's only a few cars nobody would have to touch the steering wheel, but as the number of cars increases it gets more complicated, both per car and in aggregate.

[jjk166]

Satellites do travel in lanes (orbits) and do have brakes (maneuvering thrusters), so the analogy is pretty spot on. Changing your speed (the magnitude of your velocity) to avoid a collision is also a collision avoidance maneuver, functionally equivalent to changing the direction of your velocity.

[toss1]

Yes. The count also does not seem to account for the steadily increasing number of Starlink satellites (although that is increasing linearly but avoidance maneuvers are increasing exponentially).

I also wonder at what altitude are most of the maneuvers. Are they during the phase between achieving orbit and boosting to their 550km final orbit altitude, or at the final altitude? I have a vague recollection of reading that the 550km altitude was selected partly due to low traffic, and is SpaceX' traffic itself causing the maneuvers?

Also, the maneuvers are based on orbital data several days in advance. How close are we to the point where multiple satellites maneuver simultaneously, but without accounting for the other satellite's maneuver, and wind up causing a crash?

[dgrin91]

> There’s traffic in space.

Is there? I mean obviously there are other satellites, but typically the framing has been that space and LEO is so big that it doesn't matter. That even with all the other satellites you typically don't need any sort of course correction except in very rare circumstances.

Isn't the better analogy 'I used to never need to do any swerving at all on my morning commute, but now I need to do it 600 times'?

[axus]

There's a space object and debris tracking visualization at http://astria.tacc.utexas.edu/AstriaGraph/

You can filter to "Low Earth Orbit" and play at 100x speed to get an idea of how things are moving around. There's a lot of intersecting paths, a lot of them Starlink satellite trains.

[SketchySeaBeast]

In those visualization aren't those orange spheres kilometers wide? I feel like we're still missing just how big space and the gap between the tiny objects is and that visualization blows it all out of proportion.

[dgrin91]

These visualizations are great to give you a basic sense of whats going on up there, but they do not represent any sort of realistic scale. If they did then the visualization would be boring because everything would be WAY too small.

Also it is stuck with a relatively 2D format. Are the satellites really intersecting or is there 10km of vertical distance between them? Its hard to tell with these forms of visualization.