Since the current Cluster mission is a replacement for the original Cluster spacecraft, the science payloads remain the same as on the original spacecraft.
The four Cluster spacecraft carry identical sets of 11 scientific instruments. They are designed to study space weather inside and outside the region influenced by Earth's magnetic field - the magnetosphere. By using the same instruments on all four spacecraft, scientists will obtain the first detailed, three-dimensional picture of what happens within different regions of the Earth's magnetic shield.
Each instrument is built by a team under the leadership of a Principal Investigator (PI). Most of the PIs have worked on the same instrument for both missions.
The Cluster scientific community includes the ESA Project Scientist, Philippe Escoubet, 11 Principal Investigators and more than 200 Co-Investigators from ESA member states, the United States, Canada, China, the Czech Republic, Hungary, India, Israel, Japan and Russia.