From Bryn Glover, Kirkby Malzeard, North Yorkshire, UK
Rocket launches are deemed environmentally OK if hydrogen is used as rocket fuel, because it doesn’t add to the carbon dioxide burden. However, the world must cut the total energy it consumes, and so any non-fossil fuel, such as hydrogen, ought to be used to replace fossil fuels in everyday life, not for a new space race (25 January, p 12).
