As the space shuttle Atlantis landed this morning, ending NASA’s shuttle program after 30 years without another method for astronauts to get into space on American-led missions, some are asking if this is a great leap forward for the space agency, or a small step back for manned space travel. That subject fascinates Pat Duggins, the news director of Alabama Public Radio. His soon to be released book “Trailblazing Mars: NASA’s Next Giant Leap” looks at the future of space travel.