{"assessment":{"best_window":{"end":"2025-09-18T02:35Z","end_local":"05:35","hours":8.5,"label":"good","mean_quality":0.91,"start":"2025-09-17T18:05Z","start_local":"21:05"},"cost":{"altitude":0.0,"clouds":0.71,"darkness":2.45,"moon":0.2},"formula":"astronomy = 100 * min(1, sky_hours / reference_hours) * peak_sky; overall = astronomy * score_weather / 100 (null when the weather is unknown)","hard_limit":null,"headline":"Worth it","hourly":[{"alt":null,"cloud":10,"high":0,"iso":"2025-09-17T17:00Z","label":"poor","low":7,"mid":6,"moon_alt":-20,"precip":0.0,"q":0.13,"rh":65,"sky":"nautical twilight","temp":7.1,"time":"20:00","wind":14.0},{"alt":null,"cloud":7,"high":0,"iso":"2025-09-17T18:00Z","label":"marginal","low":0,"mid":7,"moon_alt":-25,"precip":0.0,"q":0.46,"rh":66,"sky":"astronomical twilight","temp":6.4,"time":"21:00","wind":13.5},{"alt":null,"cloud":0,"high":0,"iso":"2025-09-17T19:00Z","label":"good","low":0,"mid":0,"moon_alt":-27,"precip":0.0,"q":1.0,"rh":70,"sky":"night","temp":6.0,"time":"22:00","wind":13.9},{"alt":null,"cloud":8,"high":0,"iso":"2025-09-17T20:00Z","label":"good","low":8,"mid":0,"moon_alt":-27,"precip":0.0,"q":0.91,"rh":78,"sky":"night","temp":5.4,"time":"23:00","wind":15.4},{"alt":null,"cloud":26,"high":0,"iso":"2025-09-17T21:00Z","label":"good","low":26,"mid":0,"moon_alt":-24,"precip":0.0,"q":0.71,"rh":82,"sky":"night","temp":4.9,"time":"00:00","wind":18.3},{"alt":null,"cloud":3,"high":0,"iso":"2025-09-17T22:00Z","label":"good","low":3,"mid":0,"moon_alt":-18,"precip":0.0,"q":0.97,"rh":80,"sky":"night","temp":4.7,"time":"01:00","wind":19.7},{"alt":null,"cloud":1,"high":0,"iso":"2025-09-17T23:00Z","label":"good","low":1,"mid":0,"moon_alt":-11,"precip":0.0,"q":0.99,"rh":78,"sky":"night","temp":4.3,"time":"02:00","wind":18.4},{"alt":null,"cloud":1,"high":0,"iso":"2025-09-18T00:00Z","label":"good","low":1,"mid":0,"moon_alt":-2,"precip":0.0,"q":0.99,"rh":77,"sky":"night","temp":4.0,"time":"03:00","wind":18.1},{"alt":null,"cloud":5,"high":0,"iso":"2025-09-18T01:00Z","label":"good","low":5,"mid":0,"moon_alt":7,"precip":0.0,"q":0.88,"rh":78,"sky":"night","temp":3.8,"time":"04:00","wind":17.7},{"alt":null,"cloud":13,"high":0,"iso":"2025-09-18T02:00Z","label":"good","low":13,"mid":0,"moon_alt":18,"precip":0.0,"q":0.79,"rh":81,"sky":"night","temp":3.4,"time":"05:00","wind":16.4},{"alt":null,"cloud":8,"high":0,"iso":"2025-09-18T03:00Z","label":"marginal","low":8,"mid":0,"moon_alt":28,"precip":0.0,"q":0.41,"rh":85,"sky":"astronomical twilight","temp":2.9,"time":"06:00","wind":14.2},{"alt":null,"cloud":3,"high":0,"iso":"2025-09-18T04:00Z","label":"unusable","low":3,"mid":0,"moon_alt":39,"precip":0.0,"q":0.0,"rh":87,"sky":"civil twilight","temp":2.6,"time":"07:00","wind":12.4}],"peak_quality":1.0,"peak_sky":1.0,"quality_hours":8.3,"reasons":["daylight and twilight cost 2.5 quality-hours","cloud cover cost 0.7 quality-hours"],"reference_hours":4.0,"score":92,"score_astronomy":100,"score_weather":92,"sky_hours":9.02,"verdict":"good","verdict_astronomy":"good","weather_known":true,"windows":[{"end":"2025-09-17T16:55Z","end_local":"19:55","hours":0.5,"label":"unusable","mean_quality":0.0,"start":"2025-09-17T16:25Z","start_local":"19:25"},{"end":"2025-09-17T17:30Z","end_local":"20:30","hours":0.58,"label":"poor","mean_quality":0.13,"start":"2025-09-17T16:55Z","start_local":"19:55"},{"end":"2025-09-17T18:05Z","end_local":"21:05","hours":0.58,"label":"marginal","mean_quality":0.45,"start":"2025-09-17T17:30Z","start_local":"20:30"},{"end":"2025-09-18T02:35Z","end_local":"05:35","hours":8.5,"label":"good","mean_quality":0.91,"start":"2025-09-17T18:05Z","start_local":"21:05"},{"end":"2025-09-18T03:05Z","end_local":"06:05","hours":0.5,"label":"marginal","mean_quality":0.39,"start":"2025-09-18T02:35Z","start_local":"05:35"},{"end":"2025-09-18T03:40Z","end_local":"06:40","hours":0.58,"label":"poor","mean_quality":0.12,"start":"2025-09-18T03:05Z","start_local":"06:05"},{"end":"2025-09-18T04:05Z","end_local":"07:05","hours":0.42,"label":"unusable","mean_quality":0.0,"start":"2025-09-18T03:40Z","start_local":"06:40"}]},"calculation_version":"2026-10-10.1","forecast":[{"cloud":22,"dark":false,"high":0,"local":"19:00","low":9,"mid":17,"precip":0.0,"rh":68,"temp":8.8,"time":"2025-09-17T16:00Z","wind":14.0},{"cloud":10,"dark":false,"high":0,"local":"20:00","low":7,"mid":6,"precip":0.0,"rh":65,"temp":7.1,"time":"2025-09-17T17:00Z","wind":14.0},{"cloud":7,"dark":false,"high":0,"local":"21:00","low":0,"mid":7,"precip":0.0,"rh":66,"temp":6.4,"time":"2025-09-17T18:00Z","wind":13.5},{"cloud":0,"dark":true,"high":0,"local":"22:00","low":0,"mid":0,"precip":0.0,"rh":70,"temp":6.0,"time":"2025-09-17T19:00Z","wind":13.9},{"cloud":8,"dark":true,"high":0,"local":"23:00","low":8,"mid":0,"precip":0.0,"rh":78,"temp":5.4,"time":"2025-09-17T20:00Z","wind":15.4},{"cloud":26,"dark":true,"high":0,"local":"00:00","low":26,"mid":0,"precip":0.0,"rh":82,"temp":4.9,"time":"2025-09-17T21:00Z","wind":18.3},{"cloud":3,"dark":true,"high":0,"local":"01:00","low":3,"mid":0,"precip":0.0,"rh":80,"temp":4.7,"time":"2025-09-17T22:00Z","wind":19.7},{"cloud":1,"dark":true,"high":0,"local":"02:00","low":1,"mid":0,"precip":0.0,"rh":78,"temp":4.3,"time":"2025-09-17T23:00Z","wind":18.4},{"cloud":1,"dark":true,"high":0,"local":"03:00","low":1,"mid":0,"precip":0.0,"rh":77,"temp":4.0,"time":"2025-09-18T00:00Z","wind":18.1},{"cloud":5,"dark":true,"high":0,"local":"04:00","low":5,"mid":0,"precip":0.0,"rh":78,"temp":3.8,"time":"2025-09-18T01:00Z","wind":17.7},{"cloud":13,"dark":true,"high":0,"local":"05:00","low":13,"mid":0,"precip":0.0,"rh":81,"temp":3.4,"time":"2025-09-18T02:00Z","wind":16.4},{"cloud":8,"dark":false,"high":0,"local":"06:00","low":8,"mid":0,"precip":0.0,"rh":85,"temp":2.9,"time":"2025-09-18T03:00Z","wind":14.2},{"cloud":3,"dark":false,"high":0,"local":"07:00","low":3,"mid":0,"precip":0.0,"rh":87,"temp":2.6,"time":"2025-09-18T04:00Z","wind":12.4},{"cloud":3,"dark":false,"high":0,"local":"08:00","low":3,"mid":0,"precip":0.0,"rh":82,"temp":3.7,"time":"2025-09-18T05:00Z","wind":13.8}],"forecast_source":"history","forecast_updated_at":"2026-10-23T00:06:20Z","limits":{"good_alt":30.0,"usable_alt":20.0},"night":{"dark_from":"2025-09-17T18:00:53Z","dark_hours":8.49,"dark_to":"2025-09-18T02:30:15Z","moon":{"illumination":0.153,"phase":"waning crescent","waxing":false},"moon_free_dark_hours":6.23,"moonrise":"2025-09-18T00:15:17Z","moonset":"2025-09-17T14:27:25Z","sunrise":"2025-09-18T04:04:22Z","sunset":"2025-09-17T16:26:53Z","twilight":{"astronomical":{"end":"2025-09-17T18:00:53Z","start":"2025-09-18T02:30:15Z"},"civil":{"end":"2025-09-17T16:54:40Z","start":"2025-09-18T03:36:33Z"},"nautical":{"end":"2025-09-17T17:27:22Z","start":"2025-09-18T03:03:48Z"}},"window_end":"2025-09-18T09:00:00Z","window_start":"2025-09-17T09:00:00Z"},"night_date":"2025-09-17","site":{"elev_m":1750,"lat":41.693,"lon":24.739,"name":"NAO Rozhen"},"warnings":[]}
