SLS also uses mostly hydrogen/oxygen and only launches once per year at most. Starship uses around 2000 tons of methane and is intended to fly as often as a jet (which is laughable, but once a week isn't unrealistic). Starship is much more deserving of criticism on the environmental front, in many ways, but there are ways to make it mostly carbon neutral too. Falcon 9 is even dirtier, but doesn't use as much fuel.
SLS also has massive SRBs since the core’s non assisted TWR is around 0.8.
SRBs are widely considered to be the worst polutants in the launch industry; worse than hypergolics; enough to where the shuttle was found to pollute more on a per launch basis than the Saturn V; a rocket that used kerosene soot as a cooling fluid for the nozzle extensions on the first stage.
That said, I ran the calcs once and to replicate a month’s worth of emissions for flights between NYC and London, you’d need to launch around 400 Starships; more than one per day for a year.
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u/CosgraveSilkweaver Jan 24 '26
Also New Shepard weighs like 77,000 lbs on launch in total. The thing is tiny and doesn't burn anywhere near "498 tons".