Jupiter and Its Moons Photograph courtesy NASA This family portrait, a composite of the Jovian system, includes the edge of Jupiter (with the Great Red Spot visible) and Jupiter's four largest moons, known as the Galilean satellites. From top to bottom are Io, Europa, Ganymede, and Callisto. The smallest of these four moons, Europa is about the size of Earth's moon.
Jupiter’s moon Io and its tiny shadow sweep across the giant planet’s face back in 1999, as snapped by the Hubble Space Telescope. [Credit: John Spencer (Lowell Observatory) and NASA] Mona Evans, "Jupiter's Galilean Moons" http://www.bellaonline.com/articles/art42279.asp
Io is the first Galilean moon of Jupiter, it is slightly larger than Earth’s moon. Io experiences intense tidal heating due to its elliptical orbit and orbital resonance with Europa and Ganymede. This makes Io the most geologically active moon in our solar system.
Hubble Space Telescope observations show water vapor on Jupiter's moon Europa. If this is coming through surface cracks from Europa's subsurface ocean, it could have a lot of information on what's there. This is an artist's impression showing Europa with Jupiter in the background. (Image credit: NASA, ESA, and M. Kornmesser) Mona Evans, "Jupiter's Galilean Moons" http://www.bellaonline.com/articles/art42279.asp
Gibbous Europa-Although the phase of this moon might appear familiar, the moon itself might not. In fact, this gibbous phase shows part of Jupiter's moon Europa. ESA and NASA have together started preliminary development of the Europa Jupiter System Mission , a spacecraft proposed to better study Europa.
Jupiter moon Europa may have water geysers taller than Everest
An artist's illustration of Jupiter's icy moon Europa, with a water geyser erupting in the foreground while Jupiter appears as a backdrop. Images from the Hubble Space Telescope suggest Europa may have water plumes like Saturn's moon Enceladus. Image released Dec. 12, 2013
Europa: Huge Water Vapor Plumes Seen Erupting from Jupiter’s Moon Dec 13, 2013 by Sci-News.com An international team of astronomers using NASA’s Hubble Space Telescope has discovered strong evidence of giant water-vapor geysers shooting off of Europa, the smallest of Jupiter’s Galilean moons.
Jupiter, Europa & Callisto [Pin It] Credit: NASA/JPL/University of Arizona NASA's Cassini spacecraft captured this image on Dec. 7, 2000, just as two of Jupiter's four major moons, Europa and Callisto, were nearly perfectly aligned with each other and the center of the planet.
Gibbous Europa Credit: Galileo Project, JPL, NASA; reprocessed by Ted Stryk Although the phase of this moon might appear familiar, the moon itself might not. In fact, this gibbous phase shows part of Jupiter's moon Europa. The robot spacecraft Galileo captured this image mosaic during its mission orbiting Jupiter from 1995 - 2003. Visible are plains of bright ice, cracks that run to the horizon, and dark patches that likely contain both ice and dirt...
JUPITER’S MOONS — CLOSE-UP These four views show the great surface variety present on Jupiter’s large satellites. We see volcanic deposits on Io, ice fractures on Europa, grooved terrain on Ganymede, and impact basins on Callisto. The relative ages of these surfaces range from Io, the youngest, through Europa and Ganymede, to Callisto, the oldest. Prepared for NASA by Stephen Paul Meszaros