NASA Jet Propulsion Laboratory – Ion Propulsion Advance Technology To Power Spacecrafts [720p]
http://www.nasa.gov/centers/glenn/about/fs21grc.html
http://www.nasa.gov/centers/glenn/about/fs08grc.html
source
http://www.nasa.gov/centers/glenn/about/fs21grc.html
http://www.nasa.gov/centers/glenn/about/fs08grc.html
source
