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Letter: More ideas on how to get to the TRAPPIST-1 system (2)

Published 8 July 2026

From Richard Mellish, London, UK

Glover says “I can’t imagine how to calculate the mass of fuel that would be required” for a trip to TRAPPIST-1 and back. Surely all you need is the Tsiolkovsky rocket equation, which expresses the relationship between a rocket’s mass and the propellant required to move it, plus some assumptions about the astronauts’ needs for food, water and air.

People often say that something “isn’t rocket science”, as if rocket science is very difficult – but rocket science is really just that equation. It is rocket engineering that is difficult.

Issue no. 3603 published 11 July 2026

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