Pwyll Crater on Europa
Pwyll crater on Jupiter's moon, Europa, was photographed by the Solid State Imaging system on the Galileo spacecraft during its sixth orbit around Jupiter. This impact crater is located at 26 degrees south latitude, 271 degrees west longitude, and is about 26 kilometers (16 miles) in diameter. Lower resolution pictures of Pwyll Crater taken earlier in the mission show that material ejected by the impact can be traced for hundreds of miles across the icy surface of Europa. The dark zone seen here in and around the crater is material excavated from several kilometers (a few miles) below the surface. Also visible in this picture are complex ridges.
The two images comprising
this mosaic were taken on February 20, 1997 from a distance of 12,000
kilometers (7,500 miles) by the Galileo spacecraft. The area shown is
about 120 kilometers by 100 kilometers (75 miles by 60 miles).
Close-up of Europa's Trailing Hemisphere
This complex terrain on Jupiter's moon, Europa, shows an area centered at 12 degrees north latitude, 274 degrees west longitude, in the trailing hemisphere. As Europa moves in its orbit around Jupiter, the trailing hemisphere is the portion which is always on the moon's backside opposite to its direction of motion. The area shown is about 100 kilometers by 140 kilometers (62 miles by 87 miles). The complex ridge crossing the picture in the upper left corner is part of a feature that can be traced hundreds of miles across the surface of Europa, extending beyond the edge of the picture. The upper right part of the picture shows terrain that has been disrupted by an unknown process, superficially resembling blocks of sea ice during a springtime thaw. Also visible are semicircular mounds surrounded by shallow depressions. These might represent the intrusion of material punching through the surface from below and partial melting of Europa's icy crust. The resolution of this image is about 180 meters (200 yards); this means that the smallest visible object is about a quarter of a mile across.
This picture of
Europa was taken by Galileo's Solid State Imaging system from a distance
of 17,900 kilometers (11,100 miles) on the spacecraft's sixth orbit
around Jupiter, on February 20, 1997.
Europa Ridges, Hills, and Domes
This moderate-resolution view of the surface of one of Jupiter's moons, Europa, shows the complex icy crust that has been extensively modified by fracturing and the formation of ridges. The ridge systems superficially resemble highway networks with overpasses, interchanges and junctions. From the relative position of the overlaps, it is possible to determine the age sequence for the ridge sets. For example, while the 8-kilometer-wide (5-mile) ridge set in the lower left corner is younger than most of the terrain seen in this picture, a narrow band cuts across the set toward the bottom of the picture, indicating that the band formed later. In turn, this band is cut by the narrow 2- kilometer-wide (1.2-mile) double ridge running from the lower right to upper left corner of the picture. Also visible are numerous clusters of hills and low domes as large as 9 kilometers (5.5 miles) across, many with associated dark patches of non-ice material. The ridges, hills and domes are considered to be ice-rich material derived from the subsurface. These are some of the youngest features seen on the surface of Europa and could represent geologically young eruptions.
This area covers about
140 kilometers by 130 kilometers (87 miles by 81 miles) and is centered
at 12.3 degrees north latitude, 268 degrees west longitude. Illumination
is from the east (right side of picture). The resolution is about 180
meters (200 yards) per pixel, meaning that the smallest feature visible
is about a city block in size. The picture was taken by the Solid State
Imaging system on board the Galileo spacecraft on February 20, 1997, from
a distance of 17,700 kilometers (11,000 miles) during its sixth orbit
Mosaic of Europa's Ridges, Craters
This view of the icy surface of Europa, is a mosaic of two pictures taken by the Solid State Imaging system on board the Galileo spacecraft during a close flyby of Europa on February 20, 1997. The pictures were taken from a distance of 2,000 kilometers (1,240 miles). The area shown is about 14 kilometers by 17 kilometers (8.7 miles by 10.6 miles), and has a resolution of 20 meters (22 yards) per pixel. Illumination is from the right (east). The picture is centered at about 14.8 north latitude, 273.8 west longitude, in Europa's trailing hemisphere.
One of the youngest features seen in
this area is the double ridge cutting across the picture from the lower
left to the upper right. This double ridge is about 2.6 kilometers (1.6
miles) wide and stands some 300 meters (330 yards) high. Small craters
are most easily seen in the smooth deposits along the south margin of the
prominent double ridge, and in the rugged ridged terrain farther south.
The complexly ridged terrain seen here shows that parts of the icy crust
of Europa have been modified by intense faulting and disruption, driven
by energy from the planet's interior.
Europa Triple Band
This picture of Europa was obtained on February 20, 1997, by the Solid State Imaging system onboard the Galileo spacecraft during its sixth orbit around Jupiter. The area is centered at 9.3 degrees north latitude, 275.7 degrees west longitude, on the trailing hemisphere of Europa. As Europa moves in its orbit around Jupiter, the trailing hemisphere is the portion which is always on the moon's backside opposite to its direction of motion. The area depicted is about 32 kilometers by 40 kilometers (20 miles by 25 miles). Resolution is 54 meters (59 yards). The Sun illuminates the scene from the right (east).
A section of a triple band crosses the upper left of the
picture and extends for hundreds of miles across the surface. Triple
bands derive their name from their appearance at lower resolution as a
narrow bright band flanked by a pair of darker bands. At the high
resolution of this picture, however, the triple band is much more complex
and is composed of a system of ridges 6 kilometers (4 miles) across. Some
ridges reach heights of about 180 meters (200 yards). Other features
include a hill in the center of the picture about 480 meters (500 yards)
high. Two mounds about 6 kilometers across (4 miles) are seen in the
bottom of the picture. The ridges, hills and mounds probably all
represent uplifts of the icy crust of Europa by processes originating
from the interior.
Europa Ice Rafts
This high resolution image shows the ice-rich crust of Europa, one of the moons of Jupiter. Seen here are crustal plates ranging up to 13 kilometers (8 miles) across, which have been broken apart and "rafted" into new positions, superficially resembling the disruption of pack-ice on polar seas during spring thaws on Earth. The size and geometry of these features suggest that motion was enabled by ice-crusted water or soft ice close to the surface at the time of disruption.
The area shown is about 34 kilometers by 42 kilometers
(21 miles by 26 miles), centered at 9.4 degrees north latitude, 274
degrees west longitude, and the resolution is 54 meters (59 yards). This
picture was taken by the Galileo
spacecraft on February 20, 1997, from a distance of 5,340 kilometers
(3,320 miles) during the spacecraft's close flyby of Europa.
Close-up of Europa's Surface
This close-up view of the icy surface of Europa was obtained on December 20, 1996, by the Solid State Imaging system on board the Galileo spacecraft during its fourth orbit around Jupiter. The view is about 13 kilometers by 18 kilometers (8 miles by 11 miles) and has a resolution of 26 meters (28 yards). The Sun illuminates the scene from the east (right).
A flat smooth area about
3.2 kilometers (2 miles) across is seen in the left part of the picture.
This area resulted from flooding by a fluid which erupted onto the
surface and buried sets of ridges and grooves. The smooth area contrasts
with a distinctly rugged patch of terrain farther east, to the right of
the prominent ridge system running down the middle of the picture. The
rugged patch of terrain is 4 kilometers (2.5 miles) across and represents
localized disruption of the complex network of ridges in the area.
Eruptions of material onto the surface, crustal disruption, and the
formation of complex networks of folded and faulted ridges show that
significant energy was available in the interior of Europa. Although
small impact craters are most easily seen in the smooth area, they occur
throughout the ridged terrain seen in this view.
Jupiter's Icy Satellite Europa
This image of Europa, an icy satellite of Jupiter, was obtained from a range of 39028 miles (62089 kilometers) by the Galileo spacecraft during its fourth orbit around Jupiter and its first close pass of Europa. The image spans an area 78 miles by 244 miles (126 km by 393 km), and shows features as small as a mile (1.6 km) across. Sun illumination is from the right, revealing several ridges crossing the scene, plateaus commonly several miles (10 km) across, and patches of smooth, low-lying darker materials. No prominent impact craters are visible, indicating the surface in this location is not geologically ancient. Some ridges have gaps, and subtle textural differences in these areas indicate that missing ridge segments probably were swept away by volcanic flows. The flow deposits are probably composed mainly of water ice, the chief constituent of the surface of Europa.
Flows on Europa
The icy surface of Europa, one of the moons of Jupiter, was photographed by the Galileo spacecraft on its fourth orbit around Jupiter. The area shown here is about 77 miles (124 kilometers) by 115 miles (186 kilometers) across and shows features as small as a half a mile (800 meters) across. Thick, lobate flows, the first seen on Europa or any of the icy satellites of Jupiter, are visible in several areas, including the lower right quarter of the picture where one flow cuts across a prominent ridge. Most of the ridges on the left side of the picture appear to be partly buried or subdued by flows. The ice-rich surface of Europa suggests that the flows might also be ice, perhaps erupted onto the surface from the interior as viscous, glacierlike masses.
This picture was taken by the solid state imaging television
camera on board the Galileo spacecraft at a distance of 39,191 miles
(63,490 kilometers). The picture is centered at 319.5 degrees West,
5.11 degrees North; north is toward the top of the image with the sun
shining from the right to the left.
Macula on Europa
This image of Europa, an icy satellite of Jupiter about the size of the Earth's Moon, was obtained from a range of 11,933 kilometers (7,415 miles) by the Galileo spacecraft during its fourth orbit around Jupiter and its first close pass of Europa. The image spans 30 miles by 57 miles (48 km by 91 km) and shows features as small as 800 feet (240 meters) across. The large circular feature centered in the upper middle of the image is called a macula, and could be the scar of a large meteorite impact. The surface of Europa is composed mostly of water ice, so large impact craters on Europa could look different from large bowl-shaped depressions formed by impact into rock, such as on the Moon. On Europa's icy surface, the original impact crater has been modified into a central zone of rugged topography surrounded by circular fractures which reflect adjustments to stress in the surrounding icy crust.
Prominent Doublet Ridges on Europa
This image of Jupiter's satellite Europa was obtained from a range of 11,851 kilometers (7,364 miles) by the Galileo spacecraft during its fourth orbit around Jupiter and its first close pass of Europa. The image spans 30 miles by 57 miles (48 km x 91 km) and shows features as small as 800 feet (240 meters) across, a resolution more than 150 times better than the best Voyager coverage of this area. The sun illuminates the scene from the right. The large circular feature in the upper left of the image could be the scar of a large meteorite impact. Clusters of small craters seen in the right of the image may mark sites where debris thrown from this impact fell back to the surface. Prominent doublet ridges over a mile (1.6 km) wide cross the plains in the right part of the image; younger ridges overlap older ones, allowing the sequence of formation to be determined. Gaps in ridges indicate areas where emplacement of new surface material has obliterated pre-existing terrain.
Structurally Complex Surface of Europa
This is a composite of two images of Jupiter's icy moon Europa obtained from a range of 2,119 miles (3,410 kilometers) by the Galileo spacecraft during its fourth orbit around Jupiter and its first close pass of Europa. The mosaic spans 11 miles by 30 miles (17 km by 49 km) and shows features as small as 230 feet (70 meters) across. This mosaic is the first very high resolution image data obtained of Europa, and has a resolution more than 50 times better than the best Voyager coverage and 500 times better than Voyager coverage in this area. The mosaic shows the surface of Europa to be structurally complex. The sun illuminates the scene from the right, revealing complex overlapping ridges and fractures in the upper and lower portions of the mosaic, and rugged, more chaotic terrain in the center. Lateral faulting is revealed where ridges show offsets along their lengths (upper left of the picture). Missing ridge segments indicate obliteration of pre-existing materials and emplacement of new terrain (center of the mosaic). Only a small number of impact craters can be seen, indicating the surface is not geologically ancient.
Ridges on Europa
This is the highest resolution picture ever taken of the Jupiter moon, Europa. The area shown is about 5.9 by 9.9 miles (9.6 by 16 kilometers) and the smallest visible feature is about the size of a football field. In this view, the ice-rich surface has been broken into a complex pattern by cross-cutting ridges and grooves resulting from tectonic processes. Sinuous rille-like features and knobby terrain could result from surface modifications of unknown origins. Small craters of possible impact origin range in size from less than 330 feet (100 meters) to about 1300 feet (400 meters) across are visible.
image was taken by the solid state imaging television camera aboard the
Galileo during its fourth orbit around Jupiter, at a distance of 2060
miles (3340 kilometers). The picture is centered at 325 degrees West,
5.83 degrees North. North is toward the top of this image, with the sun
shining from the right.
Copyright © 1997 by Calvin J. Hamilton. All rights reserved.