Click or tap the chart below to show the moons at that moment.
Positions of the four Galilean moons come from the L1 theory of Lainey, Duriez and Vienne (IMCCE) as built into the astronomy-engine library, and Jupiter's position from VSOP87. The moons are computed for the moment their light left Jupiter (about 35 to 50 minutes earlier), so what you see matches what is in the eyepiece.
How it is drawn. Each moon's sideways distance from Jupiter's centre is measured along the line of right ascension, in Jupiter radii (71,492 km). On the chart, time runs down the page and the side marked E is the direction of increasing right ascension. With the eye or binoculars, facing Jupiter from the northern hemisphere, east is on the left. An ordinary astronomical telescope turns the view upside down, so east appears on the right; a star diagonal flips it left to right, leaving north up and east on the right. Pick the option that matches your instrument and check by letting Jupiter drift: it drifts towards the west edge of a fixed telescope's field.
Events. A transit is a moon crossing in front of Jupiter; a shadow transit is its black shadow crossing the cloud tops; an occultation is the moon hidden behind the planet; an eclipse is the moon in Jupiter's shadow, where it fades out even though it is beside the disc. Times are when the centre of the moon (or its shadow) crosses the edge of Jupiter or of its umbra, using Jupiter's flattened shape (polar radius 66,854 km) and its pole direction from the IAU. A moon takes a few minutes to fade or cross the edge, so treat times as good to about a minute or two.
Callisto is far enough out that in some years it misses Jupiter and its shadow altogether. When Jupiter is close to the Sun in the sky (around conjunction) nothing is observable even though events still happen.