"We're better prepared for a journey to Mars now than we were when we sent men to the moon in the 1960s, " Zubrin told CNN.

CNN: Life on Mars?

Yet while we're much better prepared, SARS still scares us ... sometimes into silence.

CNN: STORY HIGHLIGHTS

If instead we believe we're capable of heroism ourselves, we'll be better prepared to realize that potential and snap into action if and when our time comes.

CNN: What made London Samaritan so brave