Io - Galileo

False color image of Jupiter's satellite Io

This Galileo image of Jupiter's moon Io is processed with enhanced color to bring out details. The image was produced from frames taken during Galileo's close pass of Io (130,000 km) on 3 July 1999. Sulfur-rich compounds are responsible for much of the coloring. The black, brown, and red areas are volcanic centers, and the range of colors over the surface appear to indicate mixtures of silicate and sulfurous lava flows. The bright areas near the top and bottom of the image may be frost deposits at high latitudes. The surface has undergone substantial change since the Voyager images were taken in 1979 and has changed noticeably even since earlier Galileo images. Features as small as 2.6 km can be resolved in this image. Io is 3640 km in diameter and north is up. (Galileo, P-50559)
Larger image (194K) jpg

High resolution tif file ( 22M)

Location & Time Information
Date/Time (UT): 1999-07-03
Distance/Range (km): 130,000.
Central Latitude/Longitude (deg): 0.3, 137.5 W
Orbit(s): Flyby, 21st orbit of Jupiter

Imaging Information
Area or Feature Type: global view
Instrument: Solid State Imaging CCD Camera
Instrument Resolution (pixels): 800 x 800, 8 bit
Instrument Field of View (deg): 0.46 x 0.46
Filter: near-infrared, green, violet
Illumination Incidence Angle (deg): N/A
Phase Angle (deg): N/A
Instrument Look Direction: N/A
Surface Emission Angle (deg): N/A

Ordering Information
CD-ROM Volume: N/A
NASA Image ID number: P-50559
Other Image ID number: MRPS95195
NSSDC Data Set ID (Photo): NSD XD-12A
NSSDC Data Set ID (CD): N/A
Other ID: N/A


[NASA Logo] Authors/Curators:

Dave Williams,, (301) 286-1258
Code 690.1, NASA Goddard Space Flight Center
Greenbelt, MD 20771, USA

Jay Friedlander,, (301) 286-7172
Code 612.4, NASA Goddard Space Flight Center
Greenbelt, MD 20771, USA

NASA Official: Ed Grayzeck,

Last updated: 24 September 2015