Deliver

Among the three satellite internet competitors, SpaceX’s Starlink generally manages the lowest carbon emissions per internet subscriber – about 31 times larger than terrestrial equivalents – mainly because it has the most customers, so emissions per user are lower.

Amazon’s upcoming Project Kuiper constellation may deliver the worst emissions impact of the three, partly because it is expected to use Europe’s new Ariane 6 rocket system for many launches. Unlike the SpaceX Falcon 9 rocket used by Starlink and Eutelsat’s OneWeb satellites, the Ariane 6 system will use solid fuel propellant that emits more particles like aluminium oxide.
–New Scientist