PIA00144: Jupiter with Satellites Io and Europa

Jupiter with Satellites Io and Europa


Voyager 1 took this photo of Jupiter and two of its satellites (Io, left, and Europa) on Feb. 13, 1979. Io is about 350,000 kilometers (220,000 miles) above Jupiter's Great Red Spot; Europa is about 600,000 kilometers (375,000 miles) above Jupiter's clouds. Although both satellites have about the same brightness, Io's color is very different from Europa's. Io's equatorial region show two types of material -- dark orange, broken by several bright spots -- producing a mottled appearance. The poles are darker and reddish. Preliminary evidence suggests color variations within and between the polar regions. Io's surface composition is unknown, but scientists believe it may be a mixture of salts and sulfur. Europa is less strongly colored, although still relatively dark at short wavelengths. Markings on Europa are less evident than on the other satellites, although this picture shows darker regions toward the trailing half of the visible disk. Jupiter is about 20 million kilometers (12.4 million miles) from the spacecraft. At this resolution (about 400 kilometers or 250 miles) there is evidence of circular motion in Jupiter's atmosphere. While the dominant large-scale motions are west-to-east, small-scale movement includes eddy-like circulation within and between the bands. This photo was assembled from three black and white negatives by the Image Processing Lab at Jet Propulsion Laboratory.

Background Info:

JPL manages and controls the Voyager project for NASA's Office of Space Science.

Cataloging Keywords:

Name Value Additional Values
Target Jupiter Europa, Io
System Jupiter
Target Type Planet Satellite
Mission Voyager
Instrument Host Voyager 1
Host Type Flyby Spacecraft
Instrument Imaging Science Subsystem (ISS)
Extra Keywords Atmosphere, Color, Storm
Acquisition Date
Release Date 1996-01-29
Date in Caption 1979-02-13
Image Credit NASA/JPL
Source photojournal.jpl.nasa.gov/catalog/PIA00144
Identifier PIA00144