Samantha Cristoforetti and Alexander Gerst parabolic flight training

ESA astronauts Samantha Cristoforetti and Alexander Gerst during a parabolic flight in 2011. During a three hour flight, the an Airbus A300 Zero-g aircraft and its occupants experience 30 parabolas. Each parabola lasts about one minute, of which the microgravity phase lasts some 20 seconds.