it can create a magnetic field around the moon that disrupts the planet’s magnetic field. That is a leading piece of evidence for Europa’s subsurface ocean. But that alone is not enough.

In the 1990s, however, NASA's Galileo spacecraft captured magnetic measurements near Callisto that suggested that its ice shell surface—much like that of Europa, another moon of Jupiter—may ...

Europa is objectively one of the most badass ... we saw those peculiar signals in both the magnetic field and plasma wave data that no one seemed to have explained before," Jia said.