The BepiColombo spacecraft stack undergoing one of the vibration tests to mimic the forces and accelerations experienced during launch into space. This series of tests had to prove that the spacecraft was free from defects and ready to be launched.

The stack is shown in launch configuration, with the Mercury Transfer Module at the bottom, Mercury Planetary Orbiter in the middle (with antenna seen facing the camera), and the Mercury Magnetospheric Orbiter’s Sunshield and Interface Structure at the top (the Mercury Magnetospheric Orbiter sits inside during the cruise to Mercury).

During the test run shown in this video, which was carried out in ESA’s test centre on 26 June 2017, the spacecraft was shaken from side to side for just over one minute, during which the frequency of vibrations increased from rest to 100 Hz. At the lowest frequencies the spacecraft movement amplitude at its base was largest (+/- 6 mm); it then continually decreased as the frequency continued to rise, to keep the accelerations within the targeted limits.

The dynamic response of the tall structure can be seen at the lowest frequencies where the eye can follow the movements. At frequencies higher than 25–30 Hz, the eye cannot see it anymore, giving the impression it is at rest.