The final frontier of environmental science

摘要

Wherever you look,it's hard to escape the fact that flying is bad for the environment.Whether it's the high-profile targeting of London City Airport by Extinction Rebellion earlier this year,or Air New Zealand attempting to reduce its impact via edible cups,it's more than apparent that the public's consciousness is firmly fixed on this mode of travel.But for all this attention,there doesn't seem to be that much of a focus on another,quite polluting form of transport-that which goes into space.As with aeroplanes,much of the emissions of space transport come from their fuel.Rockets generally use a refined form of kerosene known as RP-1,especially in their earlier stages.For example,SpaceX's Falcon 9 rocket uses just over 146,000 litres in its first stage,and overall,this means it produces nearly 425 tonnes of carbon dioxide for every rocket that launches.In comparison,a return flight from London to Sydney makes around 5.1 tonnes of carbon per passenger,so one rocket launch is the equivalent of sending 83 people on holiday.