Occult occultations, computed
Location

Jupiter's moons in October 2027

Io · Europa · Ganymede · Callisto

Jupiter's four big moons put on a show every night: they slip behind the planet and into its shadow, cross its face, and drag their shadows across the cloud tops. Any telescope shows it. Pick your place: the calendar and the nights keep only what your sky shows.

Where the moons are

Jupiter · October 2027

Jupiter's equator horizontal, east to the left as in binoculars. Drag through the month, or tap any event below to jump there; full screen (⤢) steps through a single night a minute at a time. Moons behind the planet fade, a moon in Jupiter's shadow is an empty ring, and a shadow on the disc is placed from the listed times. Positions ±0.1 Jupiter radii — for the picture; the times come from JPL.

Events

12 events you can see from New Delhi this month, on 11 nights

Mon
Tue
Wed
Thu
Fri
Sat
Sun
1
2
3
4
5
6271
8
9
10
11
12
131141151161
17
181
19
20
21
221
23
24
25
26
27
28
291301311
behind the planetin its shadowcrossing its faceshadow on the planet

Times in IST, when the moon's centre crosses the edge — as almanacs list them. A night runs from noon to noon. Tap an event to see it in the diagram.

Night of Wed 6 Oct

  1. Ganymede's shadow crosses Jupiter
    01:59 enters → 05:24 leaves · 3 h 25 min
    Jupiter below the horizon
  2. Io's shadow crosses Jupiter
    05:30 enters → 07:47 leaves · 2 h 17 min
    Jupiter 17° up · dusk

Night of Thu 7 Oct

  1. Io behind Jupiter
    disappears unseen → 05:32 reappears · 2 h 17 min
    Jupiter 18° up · dusk

Night of Wed 13 Oct

  1. Ganymede's shadow crosses Jupiter
    05:51 enters → 05:55 leaves · 4 min
    Jupiter 27° up · dusk

Night of Thu 14 Oct

  1. Io in Jupiter's shadow
    04:33 disappears → reappears unseen · 2 h 16 min
    Jupiter 10° up · dark sky

Night of Fri 15 Oct

  1. Io crosses Jupiter
    02:35 enters → 04:52 leaves · 2 h 17 min
    Jupiter below the horizon

Night of Sat 16 Oct

  1. Europa's shadow crosses Jupiter
    05:45 enters → 08:27 leaves · 2 h 43 min
    Jupiter 27° up · dusk

Night of Mon 18 Oct

  1. Europa behind Jupiter
    disappears unseen → 05:05 reappears · 2 h 47 min
    Jupiter 20° up · dark sky

Night of Fri 22 Oct

  1. Io crosses Jupiter
    04:35 enters → 06:51 leaves · 2 h 17 min
    Jupiter 16° up · dark sky

Night of Fri 29 Oct

  1. Io's shadow crosses Jupiter
    05:43 enters → 07:56 leaves · 2 h 14 min
    Jupiter 35° up · dusk

Night of Sat 30 Oct

  1. Io behind Jupiter
    disappears unseen → 05:58 reappears · 2 h 16 min
    Jupiter 39° up · dusk

Night of Sun 31 Oct

  1. Ganymede in Jupiter's shadow
    03:47 disappears → 07:10 reappears · 3 h 23 min
    Jupiter 12° up · dark sky

Reading the list

Times are for the moment the moon's centre crosses the edge of Jupiter or of its shadow, the convention of published tables; the moon's own disc takes a few minutes to cross. A start or end marked unseen happens behind Jupiter or inside its shadow. “Only what I can see” keeps events with Jupiter more than 10° up in a dark sky. Positions are from JPL DE431 and the jup365 satellite ephemeris, Jupiter as an oblate spheroid with its shadow cone. Mutual-event brightness drops assume uniform discs and are estimates. Events are geocentric — the same instant everywhere on Earth to well under a second.