Open cluster M39 shines<\/a><\/p>\nJupiter\u2019s largest moon, Ganymede, transits the gas giant\u2019s disk this morning. Some part of the event, which lasts more than three hours in total, is visible for all U.S. observers.\u00a0<\/p>\n
Jupiter is currently in Leo, rising around 3 A.M. local daylight time. The bright planet shines at magnitude \u20131.9, outshining 1st-magnitude Regulus, the Lion\u2019s brightest star, which lies to Jupiter\u2019s east and follows it up into the eastern sky. Through a telescope, the gas giant\u2019s disk spans 33\u201d. For those in the eastern half of the U.S., the planet is flanked by two moons on each side as it rises: Callisto and Ganymede on the east, and Io and Europa on the west. Ganymede is closing in on the eastern limb and its transit begins at 5:24 A.M. EDT. It continues across the disk as the hours pass and the sky brightens, until those in the western portion of the country see Ganymede finally exit the disk at 6:02 A.M. PDT.<\/p>\n
But Ganymede isn\u2019t the only moon to watch: Not long before Ganymede reaches a halfway point across the disk, Io winks out of view on Jupiter\u2019s western side as it passes into the planet\u2019s long, dark shadow around 5:45 A.M. CDT (just before or around sunrise on the East Coast). It is occulted by the planet about an hour later, and won\u2019t reappear until after sunrise on the West Coast.\u00a0<\/p>\n
Speaking of sizable satellites, Saturn\u2019s largest moon, Titan, sits just to the planet\u2019s southwest today, and to its southeast tomorrow night. With the bright satellite so close to the ringed world, it\u2019s a great chance to easily view both together.\u00a0<\/p>\n
Sunrise: 6:54 A.M.
Sunset: 6:45 P.M.
Moonrise: 8:09 P.M.
Moonset: 10:22 A.M.
Moon Phase: Waning gibbous (86%)
*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 10 P.M. local time from the same location.\u00a0<\/p>\n
Alison Klesman\u00a0is senior editor of\u00a0Astronomy\u00a0magazine. She holds a Ph.D. in astronomy and has studied a variety of topics, from minor planets to supermassive black holes.<\/p>\n","protected":false},"excerpt":{"rendered":"Back to Article List The gas giant\u2019s largest moon spends more than three hours crossing the jovian disk,…\n","protected":false},"author":2,"featured_media":615227,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[7],"tags":[111,139,69,12839,147,62517],"class_list":["post-615226","post","type-post","status-publish","format-standard","has-post-thumbnail","category-science","tag-new-zealand","tag-newzealand","tag-nz","tag-observing","tag-science","tag-sky-tonight"],"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/posts\/615226","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/comments?post=615226"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/posts\/615226\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/media\/615227"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/media?parent=615226"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/categories?post=615226"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/tags?post=615226"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
![\"Telescopic](\"https:\/\/www.newsbeep.com\/nz\/wp-content\/uploads\/2026\/09\/jupiter-closeup-09292026.png\")
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