Having re-usable parts is the obvious bit. But actually the worst part for the environment from a lot of rockets is the solid fuel boosters, those leave a ton of weird stuff in the atmosphere that a liquid fueled thing wouldn’t (like the Falcon Heavy, Starship, Delta 4 Heavy, New Glenn, Long March 9 and 10…)
Even Starship is going to leave a lot of CO2 behind, but they could technically make their own methane and be carbon neutral, but they aren’t as they can’t make enough of it fast enough for their plans, even if they do make some.
Interestingly apparently water vapor from rocket launches can be similarly harmful to CO2. Water vapor doesn’t usually get into the upper atmosphere, and has a hard time exiting, but still acts as a greenhouse gas.
Having re-usable parts is the obvious bit. But actually the worst part for the environment from a lot of rockets is the solid fuel boosters, those leave a ton of weird stuff in the atmosphere that a liquid fueled thing wouldn’t (like the Falcon Heavy, Starship, Delta 4 Heavy, New Glenn, Long March 9 and 10…)
Even Starship is going to leave a lot of CO2 behind, but they could technically make their own methane and be carbon neutral, but they aren’t as they can’t make enough of it fast enough for their plans, even if they do make some.
Interestingly apparently water vapor from rocket launches can be similarly harmful to CO2. Water vapor doesn’t usually get into the upper atmosphere, and has a hard time exiting, but still acts as a greenhouse gas.
Wow, we really cant catch a break on getting off this rock without consequences.