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!
Details in radiation belts close to Jupiter are mapped from measurements that NASA's Cassini spacecraft made of radio emission from high-energy electrons moving at nearly the speed of light within the belts.
The three views show the belts at different points in Jupiter's 10-hour rotation. A picture of Jupiter is superimposed to show the size of the belts relative to the planet. Cassini's radar instrument, operating in a listen-only mode, measured the strength of microwave radio emissions at a frequency of 13.8 gigahertz (13.8 billion cycles per second or 2.2 centimetre wavelength). The results indicate the region near Jupiter is one of the harshest radiation environments in the solar system.
From Earth-based radio telescopes, the telltale radio emissions would be swamped out by heat-generated radio emissions from Jupiter's atmosphere, but Cassini was close enough to Jupiter in January 2001 to differentiate between the emissions from the radiation belts and those from the atmosphere.
The belts appear to wobble as the planet turns because they are controlled by Jupiter's magnetic field, which is tilted in relation to the planet's poles.