Two plots showing the rate of close encounters closer than 1km versus altitude. Again, Starlink really stands out as having the highest close encounter rate, which is not surprising given the high densities.

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   Prof. Sam Lawler (sundogplanets@mastodon.social)'s status on Wednesday, 01-Jul-2026 04:21:53 JST Prof. Sam Lawler

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   Everything in Low Earth Orbit is travelling at essentially the same speed. So you can take this density plot, and turn it in to a close encounters plot. The heart of the paper is doing that calculation in two different ways, one analytic, and one numerical.

   In Starlink's orbit, the densest part of orbit, close encounters closer than 1 km happen every half hour or so. 1km sounds like a large distance, but remember the speeds are 7 km per SECOND. That is scary-close.