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 topicThank you for liking
You have already liked this page, you can only like it once!
Shear flow motion in a complex plasma fluid in weightlessness on the International Space Station. This image is part of the Plasma Kristall-4 experiment.
Plasma Kristall-4 is an International Space Station experiment that injects microscopic dust particles into a neon or argon tube to act as atom substitutes. As they float in the charged gas, they will collect negative charges as positive ions accumulate around them. As a result, they will start to repulse each other – just like atoms do in a fluid state.
Particle flow is induced through the radiation pressure from a laser beam aimed at the central part of the particle cloud.
This manipulation causes the proxy atoms to interact strongly, leading sometimes to melting. The particles in PK-4 are made of plastic.
A plasma is an electrically charged gas, a bit like lightning, that rarely occurs on Earth. It is considered to be the fourth state of matter, distinct from gas, liquid and solid matter.