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\n\t\t\t\tSeek out this easy-to-split but complex multiple star system in the Northern Crown, visible in the evening sky. \t\t\t<\/p>\n
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\n\t\t\t\t\t\tThe lovely double star Zeta Coronae Borealis (circled) lies high in the western sky this evening, just to the upper right of the curved figure of the Northern Crown. Credit: Stellarium\u2028\t\t\t\t\t<\/p>\n
Looking for a sky event this week? Check out our full\u00a0Sky This Week<\/a>\u00a0column.\u00a0<\/p>\n August 22: Titan northwest of Saturn<\/a><\/p>\n Let\u2019s check out a lovely binary star in Corona Borealis the Northern Crown. Still high in the west around 10 P.M. local daylight time, this curved constellation lies to the upper left of kite-shaped Bo\u00f6tes, whose brightest star, Arcturus, dominates the western sky.\u00a0<\/p>\n Situated in northwestern Corona Borealis, our target today is 5th-magnitude Zeta (\u03b6) Coronae Borealis, just under 6\u00b0 northeast of brighter magnitude 3.5 Delta (\u03b4) Bo\u00f6tis. Perfect for a small telescope, this star splits easily into two components separated by about 6\u201d. The brighter sun here is magnitude 5.0, while its fainter companion is magnitude 5.9. Both shine blue-white, but because they\u2019re so close, their colors may look noticeably different from each other. What hues do you see?\u00a0<\/p>\n In truth, this is likely more than a binary star system. Spectroscopic studies show that although the more easterly star (dubbed Zeta2 [\u03b62]) cannot be split, it, too, is a multi-star system with as many as four components. The data have been hard for astronomers to parse, so they\u2019re not actually sure how many stars this system could contain! If you want the gory details, check out this star\u2019s page on the late stellar astronomer Jim Kaler\u2019s STARS website<\/a>.\u00a0<\/p>\n Sunrise: 6:19 A.M. Tomorrow morning\u2019s observation is a challenge, but if you\u2019ve got a large scope or have some astroimaging experience, it\u2019s one you\u2019ll want to try.\u00a0<\/p>\n Saturn\u2019s moon Iapetus has a two-toned surface, with one hemisphere much brighter than the other. Iapetus is also tidally locked to Saturn \u2014 as it orbits, it slowly rotates so that the same side always faces its parent planet. But from our point of view here on Earth, we get to see the changing faces of the moon as it turns in time with its orbital motion. At western elongation, when it reaches its farthest point west of the ringed planet, its brighter hemisphere is turned earthward and it is at its brightest, around magnitude 10. On the other side of its orbit, at eastern elongation, its darker side faces us and the moon plunges to 12th magnitude.\u00a0<\/p>\n Iapetus reaches eastern elongation August 24, when it is at its faintest. That already makes it harder than usual to spot, but the difficulty is increased by its large distance from Saturn as well. You\u2019ll find it some 9.4\u2019 east of the planet. Because it is both faint and far from Saturn, it will be challenging to spot visually, but dark skies and a large telescope will aid your efforts. It should show up on astrophotos, too, so give that a try if you\u2019ve got the setup.\u00a0<\/p>\n \t\tIapetus is faint and sits far from Saturn today, but see if you can spot \u2014 or image \u2014 it as it reaches greatest eastern elongation. East is left and north is up in this view. Only moons brighter than about 12th magnitude are shown here; note their positions may be different if you\u2019re observing at a different time. Credit: Stellarium\/Oleg Pluton<\/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 Seek out this easy-to-split but complex multiple star system in the Northern Crown, visible…\n","protected":false},"author":2,"featured_media":602035,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[7],"tags":[61,60,7882,82,44123],"class_list":["post-602034","post","type-post","status-publish","format-standard","has-post-thumbnail","category-science","tag-ie","tag-ireland","tag-observing","tag-science","tag-sky-tonight"],"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/posts\/602034","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/comments?post=602034"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/posts\/602034\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/media\/602035"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/media?parent=602034"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/categories?post=602034"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/tags?post=602034"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
Sunset: 7:45 P.M.
Moonrise: 5:29 P.M.
Moonset: 1:30 A.M.
Moon Phase: Waxing gibbous (85%)
*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![\"A](\"https:\/\/www.newsbeep.com\/ie\/wp-content\/uploads\/2026\/08\/Iapetus-08242026.png\")
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