Skip Navigation: Avoid going through Home page links and jump straight to content
spacer spacer spacer
spacer spacer spacer
spacer
NASA Logo    + View the NASA Portal  
Near Earth Object Program
spacer
spacer spacer spacer
spacer
NEO Basics Search Programs Discovery Statistics Accessible NEAs News Frequently Asked Questions
spacer
spacer spacer spacer
spacer
Orbit Diagrams Orbit Elements Close Approaches Impact Risk Images Related LInks
spacer
spacer spacer spacer
spacer

IMAGES OF IMPACT CRATER CHAINS ON CALLISTO

A portion of a chain of impact craters on Jupiter's moon Callisto is seen in this image taken by the Galileo spacecraft on November 4, 1996. This crater chain on Callisto is believed to result from the impact of a split object, similar to the fragments of Comet Shoemaker- Levy 9 which smashed into Jupiter's atmosphere in July of 1994.
callisto1_s.jpg

Impact Crater Chain On Callisto
Galileo Image
November 4, 1996

This high- resolution view, taken by Galileo's solid state imaging television camera during its third orbit around Jupiter, is of Callisto's northern hemisphere at 35 degrees north, 46 degrees west, and covers an area of about eight miles (13 kilometers) across. The smallest visible crater is about 140 yards (130 meters) across. The image was taken at a range of 974 miles (1,567 kilometers).

On a global scale, Callisto is heavily cratered, indicating the great age of its surface. At the scale of this image, it was anticipated that the surface would be heavily cratered as well; however, there is a surprising lack of small craters, suggesting that one or more processes have obliterated these and other small-scale features. For example, downslope movement of ice-rich debris could bury small craters. The bright slopes visible in this picture represent places where downslope movement has taken place, exposing fresh ice surfaces.

The Jet Propulsion Laboratory manages the Galileo mission for NASA's Office of Space Science, Washington, DC.

callisto2_s.jpg

Gipul Catena Crater Chain On Callisto
Voyager 1 Image
March 1979

This Voyager 1 image of Gipul Catena, on Callisto, was obtained in March, 1979. Seven other crater chains have been mapped on Callisto to date. The discovery of Shoemaker-Levy 9 in 1993 solved the mystery of the origin of these chains. These chains formed when the fragments of comets split by Jovian tides hit the large Jovian satellites. Crater size and chain morphologies are being studied to determine the masses of comet fragments and nuclei and to assess models for the break up of comet nuclei. Gipul Catena is 620 km long and located near Callisto's north pole.

callisto3_s.jpg

Impact Crater Chain On Callisto
Voyager Image
Photo Credit:
Paul Schenk/Lunar & Planetary Institute

This image taken by the Voyager spacecraft of an unnamed crater chain is one of the longest of 12 or so such chains on Callisto, one of Jupiter's 4 planet-sized satellites. It is 360 kilometers long and the largest individual crater is approximately 24 kilometers across. Jay Melosh and Paul Schenk, reporting in the October 21, 1993, issue of Nature, propose that these and similar mysterious crater chains on Ganymede and Callisto probably formed from the past impact of comets tidally disrupted during close passage of Jupiter, similar to comet Shoemaker-Levy 9 which will strike Jupiter in July, 1994. They conclude that tidal splitting of comets is relatively common and can occur roughly once per century.

Menu
FIRST GOV   NASA Home Page Site Manager: Don Yeomans
Webmaster: Ron Baalke
Last Updated:
Feedback Credits Privacy Mailing List NASA