NASA’s Juno spacecraft captured this view of Jupiter during the mission’s 40th close pass by the giant planet on Feb. 25, 2022. The large, dark shadow on the left side of the image was cast by Jupiter’s moon Ganymede.
Citizen scientist Thomas Thomopoulos created this enhanced-color image using raw data from the JunoCam instrument (Figure A). At the time the raw image was taken, the Juno spacecraft was about 44,000 miles (71,000 kilometers) above Jupiter’s cloud tops, at a latitude of about 55 degrees south, and 15 times closer than Ganymede, which orbits about 666,000 miles (1.1 million kilometers) away from Jupiter.
An observer at Jupiter’s cloud tops within the oval shadow would experience a total eclipse of the Sun. Total eclipses are more common on Jupiter than Earth for several reasons. Jupiter has four major moons (Galilean satellites) that often pass between Jupiter and the Sun: in seven days, Ganymede transits once; Europa, twice; and Io, four times. And since Jupiter’s moons orbit in a plane close to Jupiter’s orbital plane, the moon shadows are often cast upon the planet.
JunoCam captured this image from very close to Jupiter, making Ganymede’s shadow appear especially large. Figure B, created by citizen scientist Brian Swift using JunoCam data, illustrates the approximate geometry of the visible area, projected onto a globe of Jupiter.
Image data: NASA/JPL-Caltech/SwRI/MSSS
Image processing by Thomas Thomopoulos © CC BY (Figure A)
JunoCam’s raw images are available for the public to peruse and process into image products at https://missionjuno.swri.edu/junocam/processing. More information about NASA citizen science can be found at https://science.nasa.gov/citizenscience and https://www.nasa.gov/solve/opportunities/citizenscience.
More information about Juno is at https://www.nasa.gov/juno and https://missionjuno.swri.edu. For more about this finding and other science results, see https://www.missionjuno.swri.edu/science-findings.