PIA02862: Ganymede and Jupiter

Ganymede and Jupiter


The solar system's largest moon, Ganymede, is captured here alongside the planet Jupiter in a color picture taken by NASA's Cassini spacecraft on Dec. 3, 2000.

Ganymede is larger than the planets Mercury and Pluto and Saturn's largest moon, Titan. Both Ganymede and Titan have greater surface area than the entire Eurasian continent on our planet. Cassini was 26.5 million kilometers (16.5 million miles) from Ganymede when this image was taken. The smallest visible features are about 160 kilometers (about 100 miles) across.

The bright area near the south (bottom) of Ganymede is Osiris, a large, relatively new crater surrounded by bright icy material ejected by the impact, which created it. Elsewhere, Ganymede displays dark terrains that NASA's Voyager and Galileo spacecraft have shown to be old and heavily cratered. The brighter terrains are younger and laced by grooves. Various kinds of grooved terrains have been seen on many icy moons in the solar system. These are believed to be the surface expressions of warm, pristine, water-rich materials that moved to the surface and froze.

Ganymede has proven to be a fascinating world, the only moon known to have a magnetosphere, or magnetic environment, produced by a convecting metal core. The interaction of Ganymede's and Jupiter's magnetospheres may produce dazzling variations in the auroral glows in Ganymede's tenuous atmosphere of oxygen.

Background Info:

Cassini is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Cassini mission for NASA's Office of Space Science, Washington, D.C.

Cataloging Keywords:

Name Value Additional Values
Target Jupiter Ganymede, Mercury, Pluto, Saturn, Titan
System Jupiter Pluto, Saturn
Target Type Planet Dwarf Planet, Satellite
Mission Cassini-Huygens Galileo, Voyager
Instrument Host Cassini Orbiter
Host Type Orbiter Flyby Spacecraft
Instrument Imaging Science Subsystem (ISS)
Extra Keywords Atmosphere, Color, Crater, Magnetosphere, Water
Acquisition Date
Release Date 2000-12-23
Date in Caption 2000-12-03
Image Credit NASA/JPL/University of Arizona
Source photojournal.jpl.nasa.gov/catalog/PIA02862
Identifier PIA02862