Jupiter moon Europa named after Jupiter's mythological “irregular loves”

Europa is, along with Ganymede, Io, and Callisto, one of the four Galilean satellites of the planet Jupiter in “our” solar system [1-3]. Europa's discovery is claimed by the two astronomers Galileo Galilei (note the term Galilean satellites) and Simon Marius, but the name for this Jupiter moon was suggested by a third astronomer, Johannes Kepler [4]:

Scientific competition and jockeying for political support are nothing new in astronomy; they are not even new when it comes to studying Jupiter and its satellites. Four hundred years ago, Galileo Galilei and German astronomer Simon Marius both claimed to have been the first to spot the planet's four large moons (Europa, Ganymede, Callisto, and Io). Galileo proposed naming the moons after his powerful patrons, the Medicis, in a bid to win favor and funding. Not to be outdone, Marius suggested they be called the Brandenburgian stars, after his patrons. Neither nomenclature caught on.
Years later, at a fair in Regensburg, [at the Danube river in Bavaria,] Germany, Marius ran into the famed astronomer Johannes Kepler, who jokingly suggested the satellites instead be named after Jupiter's mythological “irregular loves”—three maidens and one youth who were seduced by the king of the gods. Eventually those names stuck (although Galileo, not Marius, does get credit for the discovery in today's textbooks, because he published first).

References
[1] Chapter 9 The Voyager Encounters by Bradford A. Smith, pp. 107-130 in [2].
[2] J. Kelly Beatty and Andrew Chaikin (Editors): The New Solar System. Third Edition, Cambridge University Press & Sky Publishing Corporation, Cambridge, Massachusetts, 1990.
[3] Imke de Pater and Jack J. Lissauer: Planetary Sciences. Cambridge University Press, Cambridge, United Kingdom, 2001; pp. 193-201.
[4] Andrew Lawler: Is This the Best Place to Find Life in the Solar System? • NASA is gambling $4 billion that something is stirring beneath the ice of Jupiter's bizarre moon Europa. Discover Magazine September 2009, pp. 42-47.