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The visualisation is cool. I've never seen the debris fields visualized before. They look like scars. Might be neat to see a viz including the geo synchronous and sun synchronous orbits. Should show up as seemingly dense, but far away.
Those large red blobs are not visualizations of debris fields. You can toggle them off as "instruments", and debris is actually toggled off by default.
Just a reminder to everybody that we are competitively sprinting towards the brick wall of Kessler Syndrome by building out mega-constellations between about 600km and 1600km, sacrificing humanity's future in order to save a small amount of money right now using lower altitude orbits. Even Starlink is arguably flying too high, but the attempt to compete with them at 1000km where satellites will be causing secondary a…
> sacrificing humanity's future in order to save a small amount of money right now using lower altitude orbits Kessler is more analogous to pollution than a brick wall. Specific orbits get trashed by a cascade, not the entire sky.
But then, debris start to decay, and they decay unevenly, polluting all orbits lower than that. As this debris spreads to a crowded lower orbit it generates additional collisions.
Orbits are cleared to lower orbits according to mass cross section at roughly 10x the rate for every 100km altitude drop. So everything that decays from an accumulation of higher orbits has to eventually pass through a 300km circular orbit, but it's relatively safe because it spends so little time there.
Going full exponential cascade at 1000km might increase the number of impactors by a millionfold, though, which then proceed to rain down over the years on lower orbits.
Just a reminder to everybody that we are competitively sprinting towards the brick wall of Kessler Syndrome by building out mega-constellations between about 600km and 1600km, sacrificing humanity's future in order to save a small amount of money right now using lower altitude orbits. Even Starlink is arguably flying too high, but the attempt to compete with them at 1000km where satellites will be causing secondary a…
How is Starlink flying too high? Their orbital decay is something like 5 years right?
Three things about that -
Profitability generates competition, which may or may not respect precedent. Right now Starlink is only really worried about collisions with other parts of Starlink. We cannot afford a Starlink-inspired future to happen at 600km.
Debris generating events can spin out an object with much higher cross sectional mass than an intact satellite. Think of it in terms of what we use drag for on Earth, like a kid building kites. A heavy metal bolt works worse as a kite than a long thin panel.
These calendar decay timelines are blind to density. If there are a billion satellites with a natural lifespan of 5 years flying at 551km then they are going to go into an exponential cascade in a matter of weeks. If you plan to launch very large constellations, you need very fast decay timelines to keep that safe. It is much safer at very low altitude. There is decay 'room' for >10x as many satellites at 300km as at 400km, and >10x as many at 400km as at 500km, and >10x as many at 500km as 600km.
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It would also be nice to set aside something for manned spaceflight. Unlike with a satellite collision, if a pressure vessel gets penetrated everybody dies and nobody wants to go back. The ISS and Tianhe are going to have to deal with debris risk slowly raining down from a collision at 971km.