![\"Jupiter](\"https:\/\/www.europesays.com\/ie\/wp-content\/uploads\/2025\/10\/ASY-SM1025_06.png\")
<\/p>\n\t\t\tBack to Article List\t\t<\/p>\n
\n\t\t\t\tJupiter\u2019s moons Io and Europa overlap as they begin to transit the gas giant early this morning, following their shadows across.\t\t\t<\/p>\n
<\/p>\n
\t\t\t\t<\/p>\n
\n\t\t\t\t\t\tIo and Europa overlap (with smaller Europa appearing in front) as the two moons begin a transit of Jupiter on Oct.4. Ganymede lies east of Jupiter and Callisto lies to the west, outside the field of view shown here. Credit: Astronomy: Roen Kelly\t\t\t\t\t<\/p>\n
Jupiter\u2019s Galilean moons often transit the planet\u2019s disk one at a time \u2014 tonight, however, Io and Europa cross the disk together. The two moons even appear to partially overlap as their transits begin early this morning at 4:04 a.m. EDT, with smaller Europa passing in front of larger Io.\u00a0<\/p>\n
You\u2019ll spot bright Jupiter high in the east around this time, to the lower right of Castor and Pollux in Gemini (the planet outshines the two stars). Make sure to get your telescope out early \u2014 around 3:30 A.M. EDT, Io and Europa are approaching Jupiter from the east, but their shadows are already crossing the disk. Europa\u2019s shadow is nearest the western limb, while Io\u2019s is closer to the eastern limb (and the two moons). The moons\u2019 transit begins at 4:04 A.M. EDT, with Europa\u2019s shadow slipping off the opposite limb 13 minutes later.\u00a0<\/p>\n
Keep watching as Io quickly pulls ahead of Europa; the volcanic moon is on a smaller, closer-in orbit around Jupiter, and thus moves faster across the face of the planet. By the time Io\u2019s shadow disappears at 5:03 A.M. EDT, the two moons are well separated and Io is roughly halfway across the disk. Continue watching the moons as long as you can; the entire U.S. should be able to catch Io\u2019s exit around 6:20 A.M. EDT, although the sky is growing bright for those on the East Coast. Europa\u2019s transit ends around 5:53 A.M. CDT, right around sunrise in the Eastern time zone.\u00a0<\/p>\n
Sunrise:<\/strong>\u00a07:00 A.M.
Sunset:<\/strong>\u00a06:37 P.M.
Moonrise:<\/strong>\u00a05:25 P.M.
Moonset:<\/strong>\u00a03:53 A.M.
Moon Phase:<\/strong>\u00a0Waxing gibbous (92%)
*Times for sunrise, sunset, moonrise, and moonset are given in local time from 40\u00b0 N 90\u00b0 W. The Moon\u2019s illumination is given at 12 P.M. local time from the same location.<\/p>\n