“The Shuttle is still the most advanced machine we have to bring astronauts together with large infrastructure elements and experiments into space.
"However, having worked on crew safety and reliability after the Challenger accident and knowing that the risk associated with flying on the Shuttle is a 1% chance of not surviving a mission, this risk is not acceptable today to fly routinely to low Earth orbit. I understand the reasons for ending flights, and that it will take time to replace the Shuttle’s capabilities and achieve a higher level of confidence, even with new technologies.
"But accepting no risks at all is the highest risk today. The flame of adventure is flickering as we become averse to taking chances. Furthermore, in drafting spaceflight programmes today, we tend to be very utilitarian, and we often forget why we started human spaceflight. The earlier pioneers of space were driven by cultural influences, by politics, but mainly they were interested in science and technology; they wanted to explore, discover and understand what surrounds us.”