NASA Astronaut <a href="https://en.wikipedia.org/wiki/Thomas_Marshburn" class="extiw" title="en:Thomas Marshburn">Thomas Marshburn</a> during water survival training at Pensacola Naval Air Station. From <a rel="nofollow" class="external free" href="http://www.nasa.gov/audience/foreducators/k-4/features/F_ASCAN_Marshburn_Interview.html">http://www.nasa.gov/audience/foreducators/k-4/features/F_ASCAN_Marshburn_Interview.html</a>. NASA photo in public domain.