Mom, When Can I Go to Mars?

摘要

Charles Bolden. Nasa's adminis trator, asserted that the robotic vehicle Curiosity will "blaze a trail for human footprints on Mars." He could be right. But there is a gulf between what's tech nically feasible and what is actually achieved. Neil Armstrong made his "one small step" on the moon in 1969, only 12 years after Sputnik 1. Had the pace been sustained over the subsequent 40 years, there would be footprints on Mars already.