Evidence of a plume on Europa from Galileo magnetic and plasma wave signatures

The icy surface of Jupiter’s moon, Europa, is thought to lie on top of a global ocean1–4. Signatures in some Hubble Space Telescope images have been associated with putative water plumes rising above Europa’s surface5,6, providing support for the ocean theory. However, all telescopic detections reported were made at the limit of sensitivity of the data5–7, thereby calling for a search for plume signatures in in-situ measurements. Here, we report...