06 · Ground
Debris
10 km/s closing. One collision is a cloud; the cloud is more collisions. Design for demise, or the 800–1_200 km band keeps the gravel.
In English
Closing speeds are orbital. One smash becomes gravel; gravel becomes more smashes. That feedback is Kessler. Low shells decay. Mid-LEO keeps the mess for decades.
- Try this
- 800 km. Hit Collide a few times. Then 400 km and notice drag is the janitor.
- Keep this
- Collisions breed collisions. Design for demise.
Lab · Kessler is a feedback loop
10 km/s closing. One collision is a cloud. The cloud is more collisions. Low LEO decays. The 800–1_200 km band does not — Fengyun-1C and Cosmos–Iridium still live there as gravel.
Tracked fragments 8 · collision index 28 · this shell keeps the gravel
Fengyun-1C (2007) and Cosmos-2251/Iridium-33 (2009) still dominate some LEO shells. Collision energy is orbital, so fragments are not “dust.” They are bullets.
25-year deorbit rules and “design for demise” are this lab as policy. Graveyard orbits above GEO are the opposite bet: stay out of the road forever.