{"assessment":{"best_window":{"end":"2025-10-23T19:00Z","end_local":"22:00","hours":1.92,"label":"good","mean_quality":0.75,"start":"2025-10-23T17:05Z","start_local":"20:05"},"cost":{"altitude":0.0,"clouds":8.98,"darkness":2.46,"moon":0.0},"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":"Barely","hourly":[{"alt":null,"cloud":3,"high":0,"iso":"2025-10-23T16:00Z","label":"poor","low":3,"mid":0,"moon_alt":-1,"precip":0.0,"q":0.14,"rh":86,"sky":"nautical twilight","temp":6.4,"time":"19:00","wind":5.5},{"alt":null,"cloud":9,"high":0,"iso":"2025-10-23T17:00Z","label":"marginal","low":9,"mid":0,"moon_alt":-10,"precip":0.0,"q":0.45,"rh":93,"sky":"astronomical twilight","temp":5.3,"time":"20:00","wind":5.6},{"alt":null,"cloud":35,"high":5,"iso":"2025-10-23T18:00Z","label":"good","low":32,"mid":0,"moon_alt":-21,"precip":0.0,"q":0.61,"rh":99,"sky":"night","temp":4.9,"time":"21:00","wind":6.2},{"alt":null,"cloud":93,"high":68,"iso":"2025-10-23T19:00Z","label":"unusable","low":78,"mid":3,"moon_alt":-31,"precip":0.0,"q":0.0,"rh":99,"sky":"night","temp":5.5,"time":"22:00","wind":8.0},{"alt":null,"cloud":100,"high":98,"iso":"2025-10-23T20:00Z","label":"unusable","low":100,"mid":2,"moon_alt":-42,"precip":0.0,"q":0.0,"rh":99,"sky":"night","temp":5.6,"time":"23:00","wind":7.5},{"alt":null,"cloud":100,"high":94,"iso":"2025-10-23T21:00Z","label":"unusable","low":100,"mid":0,"moon_alt":-53,"precip":0.0,"q":0.0,"rh":99,"sky":"night","temp":5.3,"time":"00:00","wind":8.2},{"alt":null,"cloud":100,"high":100,"iso":"2025-10-23T22:00Z","label":"unusable","low":100,"mid":0,"moon_alt":-63,"precip":0.0,"q":0.0,"rh":100,"sky":"night","temp":5.4,"time":"01:00","wind":8.9},{"alt":null,"cloud":100,"high":99,"iso":"2025-10-23T23:00Z","label":"unusable","low":100,"mid":83,"moon_alt":-70,"precip":0.0,"q":0.0,"rh":100,"sky":"night","temp":5.7,"time":"02:00","wind":9.8},{"alt":null,"cloud":100,"high":8,"iso":"2025-10-24T00:00Z","label":"unusable","low":100,"mid":88,"moon_alt":-73,"precip":0.0,"q":0.0,"rh":100,"sky":"night","temp":5.7,"time":"03:00","wind":10.2},{"alt":null,"cloud":98,"high":7,"iso":"2025-10-24T01:00Z","label":"unusable","low":80,"mid":91,"moon_alt":-68,"precip":0.0,"q":0.0,"rh":99,"sky":"night","temp":5.9,"time":"04:00","wind":9.5},{"alt":null,"cloud":88,"high":9,"iso":"2025-10-24T02:00Z","label":"unusable","low":79,"mid":37,"moon_alt":-59,"precip":0.0,"q":0.0,"rh":99,"sky":"night","temp":6.3,"time":"05:00","wind":9.9},{"alt":null,"cloud":76,"high":66,"iso":"2025-10-24T03:00Z","label":"poor","low":28,"mid":4,"moon_alt":-49,"precip":0.0,"q":0.16,"rh":97,"sky":"night","temp":6.3,"time":"06:00","wind":13.1},{"alt":null,"cloud":57,"high":44,"iso":"2025-10-24T04:00Z","label":"poor","low":23,"mid":0,"moon_alt":-38,"precip":0.0,"q":0.06,"rh":96,"sky":"nautical twilight","temp":6.1,"time":"07:00","wind":13.2}],"peak_quality":0.9,"peak_sky":1.0,"quality_hours":1.89,"reasons":["cloud cover cost 9.0 quality-hours","daylight and twilight cost 2.5 quality-hours"],"reference_hours":4.0,"score":17,"score_astronomy":100,"score_weather":17,"sky_hours":10.87,"verdict":"poor","verdict_astronomy":"good","weather_known":true,"windows":[{"end":"2025-10-23T16:00Z","end_local":"19:00","hours":0.58,"label":"unusable","mean_quality":0.0,"start":"2025-10-23T15:25Z","start_local":"18:25"},{"end":"2025-10-23T16:30Z","end_local":"19:30","hours":0.5,"label":"poor","mean_quality":0.14,"start":"2025-10-23T16:00Z","start_local":"19:00"},{"end":"2025-10-23T17:05Z","end_local":"20:05","hours":0.58,"label":"marginal","mean_quality":0.48,"start":"2025-10-23T16:30Z","start_local":"19:30"},{"end":"2025-10-23T19:00Z","end_local":"22:00","hours":1.92,"label":"good","mean_quality":0.75,"start":"2025-10-23T17:05Z","start_local":"20:05"},{"end":"2025-10-24T03:00Z","end_local":"06:00","hours":8.0,"label":"unusable","mean_quality":0.0,"start":"2025-10-23T19:00Z","start_local":"22:00"},{"end":"2025-10-24T04:20Z","end_local":"07:20","hours":1.33,"label":"poor","mean_quality":0.08,"start":"2025-10-24T03:00Z","start_local":"06:00"},{"end":"2025-10-24T04:45Z","end_local":"07:45","hours":0.42,"label":"unusable","mean_quality":0.0,"start":"2025-10-24T04:20Z","start_local":"07:20"}]},"calculation_version":"2026-10-10.1","forecast":[{"cloud":9,"dark":false,"high":0,"local":"18:00","low":8,"mid":1,"precip":0.0,"rh":66,"temp":9.7,"time":"2025-10-23T15:00Z","wind":5.7},{"cloud":3,"dark":false,"high":0,"local":"19:00","low":3,"mid":0,"precip":0.0,"rh":86,"temp":6.4,"time":"2025-10-23T16:00Z","wind":5.5},{"cloud":9,"dark":false,"high":0,"local":"20:00","low":9,"mid":0,"precip":0.0,"rh":93,"temp":5.3,"time":"2025-10-23T17:00Z","wind":5.6},{"cloud":35,"dark":true,"high":5,"local":"21:00","low":32,"mid":0,"precip":0.0,"rh":99,"temp":4.9,"time":"2025-10-23T18:00Z","wind":6.2},{"cloud":93,"dark":true,"high":68,"local":"22:00","low":78,"mid":3,"precip":0.0,"rh":99,"temp":5.5,"time":"2025-10-23T19:00Z","wind":8.0},{"cloud":100,"dark":true,"high":98,"local":"23:00","low":100,"mid":2,"precip":0.0,"rh":99,"temp":5.6,"time":"2025-10-23T20:00Z","wind":7.5},{"cloud":100,"dark":true,"high":94,"local":"00:00","low":100,"mid":0,"precip":0.0,"rh":99,"temp":5.3,"time":"2025-10-23T21:00Z","wind":8.2},{"cloud":100,"dark":true,"high":100,"local":"01:00","low":100,"mid":0,"precip":0.0,"rh":100,"temp":5.4,"time":"2025-10-23T22:00Z","wind":8.9},{"cloud":100,"dark":true,"high":99,"local":"02:00","low":100,"mid":83,"precip":0.0,"rh":100,"temp":5.7,"time":"2025-10-23T23:00Z","wind":9.8},{"cloud":100,"dark":true,"high":8,"local":"03:00","low":100,"mid":88,"precip":0.0,"rh":100,"temp":5.7,"time":"2025-10-24T00:00Z","wind":10.2},{"cloud":98,"dark":true,"high":7,"local":"04:00","low":80,"mid":91,"precip":0.0,"rh":99,"temp":5.9,"time":"2025-10-24T01:00Z","wind":9.5},{"cloud":88,"dark":true,"high":9,"local":"05:00","low":79,"mid":37,"precip":0.0,"rh":99,"temp":6.3,"time":"2025-10-24T02:00Z","wind":9.9},{"cloud":76,"dark":true,"high":66,"local":"06:00","low":28,"mid":4,"precip":0.0,"rh":97,"temp":6.3,"time":"2025-10-24T03:00Z","wind":13.1},{"cloud":57,"dark":false,"high":44,"local":"07:00","low":23,"mid":0,"precip":0.0,"rh":96,"temp":6.1,"time":"2025-10-24T04:00Z","wind":13.2},{"cloud":100,"dark":false,"high":98,"local":"08:00","low":93,"mid":6,"precip":0.0,"rh":98,"temp":6.0,"time":"2025-10-24T05:00Z","wind":13.2}],"forecast_source":"history","forecast_updated_at":"2026-10-21T17:55:42Z","limits":{"good_alt":30.0,"usable_alt":20.0},"night":{"dark_from":"2025-10-23T17:00:33Z","dark_hours":10.17,"dark_to":"2025-10-24T03:10:31Z","moon":{"illumination":0.053,"phase":"waxing crescent","waxing":true},"moon_free_dark_hours":10.15,"moonrise":"2025-10-24T07:50:04Z","moonset":"2025-10-23T15:55:38Z","sunrise":"2025-10-24T04:43:38Z","sunset":"2025-10-23T15:27:39Z","twilight":{"astronomical":{"end":"2025-10-23T17:00:33Z","start":"2025-10-24T03:10:31Z"},"civil":{"end":"2025-10-23T15:55:59Z","start":"2025-10-24T04:15:13Z"},"nautical":{"end":"2025-10-23T16:28:24Z","start":"2025-10-24T03:42:44Z"}},"window_end":"2025-10-24T09:00:00Z","window_start":"2025-10-23T09:00:00Z"},"night_date":"2025-10-23","site":{"elev_m":1750,"lat":41.693,"lon":24.739,"name":"NAO Rozhen"},"warnings":[]}