This NASA website dispels the myth that there is no gravity in an orbiting spacecraft. It includes the classic diagram of a cannon fired from a mountaintop that gives a projectile various velocities and shows the various orbits that result. The site explains how a drop tower is not an "anti-gravity device."
NASA Glenn Research Center. What is Microgravity?. Cleveland: NASA Glenn Research Center, March 17, 2006. http://www.nasa.gov/centers/glenn/shuttlestation/station/microgex.html (accessed 8 February 2016).
%0 Electronic Source %D March 17, 2006 %T What is Microgravity? %I NASA Glenn Research Center %V 2016 %N 8 February 2016 %8 March 17, 2006 %9 text/html %U http://www.nasa.gov/centers/glenn/shuttlestation/station/microgex.html
Disclaimer: ComPADRE offers citation styles as a guide only. We cannot offer interpretations about citations as this is an automated procedure. Please refer to the style manuals in the Citation Source Information area for clarifications.