@sundogplanets Ok, I wasn't sure. ESA launch guidelines are pretty strict to. It has to have an orbit in which it will burn up at 5 years of deployment too.
I thought really tiny bits of space debris could achieve velocities where they too might become super dangerous.
@firn They definitely can, and if we have 100,000 cubesats that will be bad. But right now this is not the main thing I'm worrying about!
And the 5 year lifetime thing is fine when you're talking about small masses - Reentry of Starlink satellites and Falcon rocket bodies is already exceeding natural influx of metals from meteorites. What will that do to the atmosphere? Only a few people are studying that now