The European Space Agency (ESA) is Europe’s gateway to space. Its mission is to shape the development of Europe’s space capability and ensure that investment in space continues to deliver benefits to the citizens of Europe and the world.
Find out more about space activities in our 23 Member States, and understand how ESA works together with their national agencies, institutions and organisations.
Exploring our Solar System and unlocking the secrets of the Universe
Go to topicProtecting life and infrastructure on Earth and in orbit
Go to topicUsing space to benefit citizens and meet future challenges on Earth
Go to topicMaking space accessible and developing the technologies for the future
Go to topicThis photograph shows the LISA Pathfinder gold-platinum proof-mass being placed over the high sensitivity balance used at the International Bureau of Weights and Measures (BIPM, France) to measure the proof-mass's magnetic susceptibility .
Once in space, LISA Pathfinder's proof-masses will be used to detect forces as small as the weight of a typical bacterium, and test the theory of General Relativity.
The perfect proof-mass is one that responds only to the force of gravity. Therefore, scientists needed to precisely measure how the LISA Pathfinder proof-masses respond to magnetic forces so that they can compensate for this in their calculations.