NASA has just released this astonishing new image of Jupiter captured by the Juno space probe during its 40th class orbit around the giant planet. That black spot is a shadow from the Jovian moon Ganymede. From NASA:
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.
image data: NASA/JPL-Caltech/SwRI/MSSS, processing by Thomas Thomopoulos © CC BY