A new view of Europa, the sixth of Jupiter’s moons and the fourth largest, has been produced from images taken by NASA’s Galileo spacecraft in the 1990s.
The surface of Europa looms large in this newly-reprocessed color view; image scale is 1.6 km per pixel; north on Europa is at right. Image credit: NASA / JPL-Caltech / SETI Institute.
Discovered by Galileo Galilei and Simon Marius in 1610, Europa is the sixth-largest moon in the Solar System.
Europa is named after a Phoenician princess who, according to Greek mythology, Zeus saw gathering flowers and immediately fell in love with. Zeus transformed himself into a bull and carried her away to the island of Crete. He then revealed his true identity and Europa became the first queen of Crete. By Zeus, she mothered Trojan War contemporaries Minos, Rhadamanthus, and Sarpedon.
As with the other moons of Jupiter, most of what we know about Europa was learned from NASA’s historic Voyager and Galileo missions.
This newly-reprocessed view consists of images acquired by the Galileo Solid-State Imaging experiment on the spacecraft’s first and fourteenth orbits through the Jupiter system in 1995 and 1998.
It shows the largest portion of the Europa’s surface at the highest resolution.
Space imaging enthusiasts have produced their own versions of the view using the publicly available data, but NASA has not previously issued its own rendition using near-natural color.
To create the new version, the Galileo images were assembled into a realistic color view of the surface that approximates how Europa would appear to the human eye.
Color variations across the moon’s bright ice shell are associated with differences in geologic feature type and location.
For example, areas that appear blue or white contain relatively pure water ice, while reddish and brownish areas include non-ice components in higher concentrations.
The polar regions, visible at the left and right of this view, are noticeably bluer than the more equatorial latitudes, which look more white. This color variation is thought to be due to differences in ice grain size in the two locations.
Images taken through near-infrared, green and violet filters have been combined to produce this view.
The Galileo images have been corrected for light scattered outside of the image, to provide a color correction that is calibrated by wavelength.
Gaps in the images have been filled with simulated color based on the color of nearby surface areas with similar terrain types.
In addition to the newly-remastered image, a new video details why Europa is a high priority for future exploration.
Hidden beneath the icy surface is perhaps the most promising place in our Solar System beyond Earth to look for present-day environments that are suitable for life.
The Galileo mission found strong evidence that a subsurface ocean of salty water is in contact with a rocky seafloor.
The cycling of material between the ocean and ice shell could potentially provide sources of chemical energy that could sustain simple life forms.
