SIR - I am a retired aerospace engineer who worked on the design of components for the Apollo Command Module. It is a common mistake to think that humans in space conduct “space exploration” and “space science” (“The end of the Space Age”, July 2nd). Space exploration, in the sense of discovering new information about the space environment, is done with sensoring and data-gathering instruments, supported and controlled by robotic spacecraft. This was true in the earliest days of the Apollo programme, and will be true for any future human-crewed space project. Humans would not be sent anywhere in space without our first obtaining a thorough understanding of that environment.
Nor do humans carry out significant science in space. High-precision, ultra-clean instruments, designed to measure specific parts of the electromagnetic spectrum and other aspects of the space environment, are used to generate scientific data in space. Human crews would interfere with, rather than contribute to, the ability of the instruments to perform their mission. Human crews would provide biological contamination and disturb the ultra-high stability required of typical scientific instruments in space.
Al Barrett Santa Monica, California
-- http://www.economist.com/node/18956507?story_id=18956507&fsrc=rss