Bruce Murray Space Image Library
Io and Europa (MVIC only)
When this image was taken, Io was on the far side of Jupiter from New Horizons, while Europa was closer to Jupiter than New Horizons. Being on the far side of Jupiter, Io's night side is lit by sunlight reflected off of Jupiter's cloud tops. Europa's night side is not, because the side of Europa that is receiving reflected light from Jupiter is the side that is facing away from New Horizons.