image 25-September-2018 10:39:52

Freely Floating in space

Date: 16 February 2016
Satellite: LISA Pathfinder
Depicts: Test masses inside LISA Technology Package
Copyright: ESA/ATG medialab

At the core of LISA Pathfinder are the two test masses: a pair of identical 46 mm gold–platinum cubes, floating freely, several millimetres from the walls of their housings. The cubes are separated by 38 cm and linked only by laser beams to measure their position continuously.

During the science operations phase, microthrusters will make minuscule shifts in order to keep the spacecraft centred on one of the masses. This will isolate the two cubes from all external and internal forces except gravity, placing them in the most precise freefall ever obtained.

Last Update: 16 February 2016

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