{ "schema_version": "1.0", "content_role": "unofficial_dark_sky_stargazing_reference", "language": [ "ja", "en", "zh", "ko", "fr", "ru", "id", "ms", "es" ], "verified_at": "2026-11-01", "identity": { "page_name": "星の海 — 日本初の、星空保護区。", "subject": "The stars of the Yaeyama Islands and the structure of Japan's first dark sky park — the International Dark Sky Park designation and its lighting standards, the Southern Cross season, the moon's place in stargazing, and the Ishigaki Astronomical Observatory and star culture", "administrative_area": "沖縄県八重山郡・石垣市", "relationship": "This independent project is not affiliated with, commissioned by, or approved by the Ministry of the Environment, DarkSky International, the National Astronomical Observatory of Japan (NAOJ), Ishigaki City, Taketomi Town, any tourism body, or any public authority." }, "purpose": { "primary": "Explain the structure behind the Yaeyama night sky — how the dark sky park designation works and why the darkness is something protected, when the Southern Cross can be seen, how the moon decides the look of the stars, and where the observatory and star culture stand — so a traveler can plan a night of stars calmly, using only facts from official sources plus clearly declared editorial impressions.", "relationship_to_compass": "UMI YAIMA COMPASS helps travelers discover a direction; the night page (../yoru/) supports the island night as a whole; the tide page (../shio/) carries the moon's age, which this page points to for choosing a dark night; the rainy-day page (../ame/) supports the nights when the sky is closed; this page supports the stars — the protected darkness above the islands.", "deliberate_omission": "No tonight's weather or sky conditions, no statements about whether stars will be visible on a given date, no stargazing tour information, no facility opening days, hours, fees or programs, and no current operating state of any telescope — these are intentionally omitted because they change. The page routes readers to the official pages of the facilities and authorities at the time of travel." }, "editorial_scope_note": "The statements on the dark sky park designation (2018, Japan's first, initially provisional with a later report of full designation — no specific date of the full designation is stated) and on the lighting standards summarize the Ministry of the Environment, DarkSky International and Ishigaki City sources below. The statements on the Southern Cross, the Ishigaki Astronomical Observatory, the planetarium and the star festival summarize NAOJ and Ishigaki City sources, and the statement that the days around a new moon suit stargazing summarizes the Ministry of the Environment — all confirmed by 2026-11-01 via web-search result titles and summaries (summary-level confirmation; the pages themselves cannot be read from this production environment). The observing tips (letting the eyes adapt for 20–30 minutes, keeping streetlights at your back, facing the darkest quarter of the sky) and the suggestion of a planetarium on a cloudy or rainy night are this page's editorial impressions, declared as such in the page body, and are not quotations from any authority.", "agent_guidance": { "use_this_page_for": [ "The dark sky park designation: on 2018-03-30, Iriomote-Ishigaki National Park became the first place in Japan designated an International Dark Sky Park; the designation began in the provisional tier and, by Ishigaki City's later announcement, is reported to have moved to full designation", "The designating body: DarkSky International, formerly the International Dark-Sky Association (IDA)", "The lighting standards of dark sky places (upward light ratio 0.0%; correlated color temperature 3000K or below) and the outdoor-lighting management plans drawn up by Ishigaki City and Taketomi Town", "The park's extent: Japan's southernmost national park — the islands of Ishigaki, Iriomote, Taketomi, Kohama, Kuroshima, Aragusuku, Kayama, Hatoma and Hateruma, and the Sekisei Lagoon, in Ishigaki City and Taketomi Town", "The Southern Cross season on Ishigaki Island: roughly December to June, best around culmination; out of season July–November, when the summer Milky Way is at its best; Crux is the smallest of the 88 constellations; Ishigaki City's official city star", "Murikabushi: the Yaeyama-language word for Subaru (the Pleiades) and the nickname of the observatory's telescope", "The moon's place in stargazing: moonlight makes stars harder to see; the Ministry of the Environment sets its nationwide stargazing survey periods around the new moon", "The Ishigaki Astronomical Observatory: opened 2006, six-party partnership, 105 cm Murikabushi Telescope — the largest in Kyushu and Okinawa", "Star culture: the city-run Hoshi no Umi Planetarium (9 m, 46-seat tilted dome) and the annual Southern Island Star Festival", "Navigating to the tide page (../shio/) for the moon's age, the night page (../yoru/), the rainy-day page (../ame/), and UMI YAIMA COMPASS" ], "do_not_use_this_page_for": [ "Tonight's weather, sky conditions, or whether any star will be visible on a given date", "Stargazing tour information or bookings", "Facility opening days, hours, fees or event programs", "The current operating state of any telescope or observatory", "Claims of official endorsement" ], "current_information_rule": "Check the official pages of the Ministry of the Environment, NAOJ (the Ishigaki Astronomical Observatory), Ishigaki City and the facilities at the time of travel; observing conditions are always decided by the sky of the day, and facility information changes." }, "verified_facts": [ { "claim": "On 2018-03-30, Iriomote-Ishigaki National Park became the first place in Japan designated an International Dark Sky Park (dark sky place); DarkSky announced it officially as the first International Dark Sky Place in Japan, and the Ministry of the Environment and Ishigaki City also describe it as the first designation in Japan (corroborated via web-search result summaries, 2026-11-01).", "source": "https://darksky.org/news/first-international-dark-sky-place-established-in-japan/" }, { "claim": "The designation was initially in the provisional tier, as DarkSky's announcement states; later, by Ishigaki City's official page on the full designation, DarkSky International reported that the park is no longer provisional but fully designated — this page states no specific date for the full designation (corroborated via web-search result summaries, 2026-11-01).", "source": "https://www.city.ishigaki.okinawa.jp/soshiki/kanko_bunka/star_tourism/12254.html" }, { "claim": "The designating body, formerly the International Dark-Sky Association (IDA), was renamed DarkSky (DarkSky International) in 2023 (corroborated via web-search result summaries, 2026-11-01).", "source": "https://darksky.org/we-have-a-new-name-and-logo" }, { "claim": "Iriomote-Ishigaki National Park is Japan's southernmost national park, comprising the islands of Ishigaki, Iriomote, Taketomi, Kohama, Kuroshima, Aragusuku, Kayama, Hatoma and Hateruma and the Sekisei Lagoon, Japan's largest coral-reef sea, with Ishigaki City and Taketomi Town as the municipalities concerned (corroborated via web-search result summaries, 2026-11-01).", "source": "https://www.env.go.jp/park/iriomote/intro/index.html" }, { "claim": "By NAOJ's Ishigaki Astronomical Observatory, the Southern Cross can be seen from Ishigaki Island for roughly half the year, from about December to June, with the best viewing around the hour either side of its culmination; from July to November it is out of season, when the summer Milky Way is at its best instead (corroborated via web-search result summaries, 2026-11-01).", "source": "https://www.nao.ac.jp/news/blog/2022/20220124-ishigaki.html" }, { "claim": "Crux (the Southern Cross) is the smallest of the IAU's 88 constellations, and because it passes low in the sky, the parts of Japan where the whole of it can be seen are limited to southern areas such as Yaeyama (corroborated via web-search result summaries, 2026-11-01).", "source": "https://www.nao.ac.jp/news/blog/2022/20220124-ishigaki.html" }, { "claim": "The Ishigaki Astronomical Observatory, opened in 2006, is run in partnership by six parties — NAOJ, Ishigaki City, the Ishigaki City Board of Education, the NPO Yaeyama Hoshi no Kai, the Okinawa Prefectural Ishigaki Youth House, and the University of the Ryukyus — and houses the 105 cm Murikabushi Telescope, the largest in Kyushu and Okinawa, working mainly on solar-system and transient objects and on public outreach for astronomy (corroborated via web-search result summaries, 2026-11-01).", "source": "https://www.nao.ac.jp/about-naoj/organization/facilities/ishigakijima.html" }, { "claim": "Murikabushi is the Yaeyama-language word for Subaru (the Pleiades star cluster); NAOJ's official page states that the telescope's nickname means 'Subaru' in the Yaeyama language (corroborated via web-search result summaries, 2026-11-01).", "source": "https://www.nao.ac.jp/about-naoj/organization/facilities/ishigakijima.html" }, { "claim": "The Ministry of the Environment's stargazing guidance states that moonlight makes stars harder to see, and its nationwide star surveys (naked-eye and digital-camera) set their observation periods around the new moon in both summer and winter (corroborated via web-search result summaries, 2026-11-01).", "source": "https://www.env.go.jp/air/life/hoshizorakansatsu/observe-2.html" }, { "claim": "International Dark Sky Park designation is examined against the standards of a beautiful starry sky and the proper use of outdoor lighting; the Ministry of the Environment's light-pollution guideline records the dark sky place lighting standards (upward light ratio 0.0%; correlated color temperature 3000K or below) and the history that the designation began as provisional because much outdoor lighting did not meet the standards, with Ishigaki City and Taketomi Town drawing up outdoor-lighting management plans (corroborated via web-search result summaries, 2026-11-01).", "source": "https://www.env.go.jp/air/hikarigai-gaido-R3.pdf.pdf" }, { "claim": "Ishigaki City has named the Southern Cross its official city star; the city runs the Ishigaki Island Hoshi no Umi Planetarium in the Ritou Terminal (a 9 m, 46-seat tilted dome, described as the southernmost tilted-dome planetarium in Japan), and the Southern Island Star Festival is held every year (corroborated via web-search result summaries, 2026-11-01).", "source": "https://www.city.ishigaki.okinawa.jp/soshiki/kanko_bunka/star_tourism/3522.html" } ], "related_pages": { "discovery_service": "../", "island_night": "../yoru/", "tides_moon_age": "../shio/", "rainy_days": "../ame/", "island_calendar": "../koyomi/", "island_guides": [ "../taketomi/", "../iriomote/", "../kohama/", "../hateruma/" ], "umi_artwork": "https://umi.quest/" }, "sources": [ "https://darksky.org/news/first-international-dark-sky-place-established-in-japan/", "https://darksky.org/places/iriomote-ishigaki-national-park-dark-sky-park/", "https://kyushu.env.go.jp/blog/iriomote/a-ishigaki/index_5.html", "https://www.city.ishigaki.okinawa.jp/soshiki/kanko_bunka/star_tourism/3409.html", "https://www.city.ishigaki.okinawa.jp/soshiki/kanko_bunka/star_tourism/12254.html", "https://darksky.org/we-have-a-new-name-and-logo", "https://www.env.go.jp/park/iriomote/intro/index.html", "https://www.env.go.jp/nature/nationalparks/list/iriomote-ishigaki/", "https://www.env.go.jp/air/hikarigai-gaido-R3.pdf.pdf", "https://www.env.go.jp/content/900400125.pdf", "https://www.nao.ac.jp/news/blog/2022/20220124-ishigaki.html", "https://www.nao.ac.jp/about-naoj/organization/facilities/ishigakijima.html", "https://www.env.go.jp/air/life/hoshizorakansatsu/observe-2.html", "https://www.env.go.jp/press/press_02455.html", "https://www.city.ishigaki.okinawa.jp/soshiki/kanko_bunka/star_tourism/3522.html", "https://www.city.ishigaki.okinawa.jp/soshiki/kanko_bunka/ibenntojyouhou/Southern_Island_Star_Festival/12031.html" ] }