Lab Notes: Is space junk destroying the ozone layer?

Old satellites and bits of space junk regularly fall back to Earth, burning up as they pass through the atmosphere.

All this burning metal causes a chain reaction and ultimately destroys ozone molecules, which keep us safe from most of the Sun's harmful UVB rays. Could a new era of satellite "megaconstellations", like the one run by SpaceX's internet company Starlink, undo humanity's hard work repairing the ozone layer?

‌Jonathan Webb launches into this issue with Dr Alice Gorman (AKA Dr Space Junk), taking stock of just how many satellites are burning up and what ca...