So, everyone worrying about the Venus probe reentry: yes, it's not designed to burn up in the atmosphere, and that's bad.
But, remember Starlink? There's something like one Starlink per day reentering now, and they weigh more than the Venus probe! SpaceX says they will burn up completely, but now one Starlink piece has been discovered in my province. (And if they don't make it to the ground, that means that half-ton of metal and plastic is deposited in the stratosphere instead. Yum).
More than 7,000 Starlinks in orbit now, and they have permission for 42,000. Even conservatively, at peak operation, they'll dump 25x more aluminum into the stratosphere than falls naturally as they launch and burn up 20-25 sats PER DAY. What will that do? We actually don't know. That metal is already measurable. SpaceX is just running this experiment.
We need fewer satellites in orbit with longer operational lifetimes. THAT is the new engineering challenge in LEO.
LEO sat disposal is a new environmental disaster brewing, mostly because of the actions of a single private company, but really, it's everyone's operating procedure in LEO. Just burn those sats up in Earth's atmosphere when they're done! They just disappear! And if they don't, they probably won't hit anyone anyway.
Ok, this is turning rambly and I'm tired and need to put my goats in the barn. I hope the Venus probe reenters with no injuries, and just to be abundantly clear: fuck Starlink.
Prof. Sam Lawler
Murad