Footprint Reading Library The first trip outside of a spacecraft, or "space walk", was completed in 1965. Since then many astronauts have participated in space walks, but not without risks and challenges. Astronauts are in constant danger when in space. What are the risks and challenges of space walking? How do astronauts overcome them? Welcome the sights and sounds of the world with the "Footprint reading Library". Accompanied by original video material developed by "National Geographic Digital Media", This is the first non-fiction reading series to present fascinating real-world stories in three formats: print, audio and video.