{"assessment":{"best_window":{"end":"2026-04-25T01:45Z","end_local":"04:45","hours":1.25,"label":"good","mean_quality":0.89,"start":"2026-04-25T00:30Z","start_local":"03:30"},"cost":{"altitude":0.0,"clouds":1.32,"darkness":2.74,"moon":2.09},"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":43,"high":43,"iso":"2026-04-24T18:00Z","label":"poor","low":0,"mid":0,"moon_alt":65,"precip":0.0,"q":0.04,"rh":63,"sky":"nautical twilight","temp":2.2,"time":"21:00","wind":1.3},{"alt":null,"cloud":45,"high":45,"iso":"2026-04-24T19:00Z","label":"poor","low":0,"mid":0,"moon_alt":58,"precip":0.0,"q":0.28,"rh":64,"sky":"night","temp":1.8,"time":"22:00","wind":0.7},{"alt":null,"cloud":44,"high":43,"iso":"2026-04-24T20:00Z","label":"marginal","low":2,"mid":0,"moon_alt":48,"precip":0.0,"q":0.3,"rh":66,"sky":"night","temp":0.9,"time":"23:00","wind":1.3},{"alt":null,"cloud":32,"high":25,"iso":"2026-04-24T21:00Z","label":"marginal","low":9,"mid":0,"moon_alt":37,"precip":0.0,"q":0.4,"rh":67,"sky":"night","temp":0.4,"time":"00:00","wind":2.4},{"alt":null,"cloud":16,"high":13,"iso":"2026-04-24T22:00Z","label":"marginal","low":4,"mid":0,"moon_alt":26,"precip":0.0,"q":0.54,"rh":65,"sky":"night","temp":0.7,"time":"01:00","wind":2.6},{"alt":null,"cloud":5,"high":5,"iso":"2026-04-24T23:00Z","label":"good","low":0,"mid":0,"moon_alt":15,"precip":0.0,"q":0.66,"rh":66,"sky":"night","temp":0.7,"time":"02:00","wind":2.8},{"alt":null,"cloud":24,"high":24,"iso":"2026-04-25T00:00Z","label":"marginal","low":0,"mid":0,"moon_alt":5,"precip":0.0,"q":0.55,"rh":67,"sky":"night","temp":0.9,"time":"03:00","wind":0.9},{"alt":null,"cloud":0,"high":0,"iso":"2026-04-25T01:00Z","label":"good","low":0,"mid":0,"moon_alt":-5,"precip":0.0,"q":1.0,"rh":67,"sky":"night","temp":0.7,"time":"04:00","wind":1.0},{"alt":null,"cloud":0,"high":0,"iso":"2026-04-25T02:00Z","label":"marginal","low":0,"mid":0,"moon_alt":-15,"precip":0.0,"q":0.5,"rh":68,"sky":"astronomical twilight","temp":0.4,"time":"05:00","wind":1.0},{"alt":null,"cloud":0,"high":0,"iso":"2026-04-25T03:00Z","label":"unusable","low":0,"mid":0,"moon_alt":-22,"precip":0.0,"q":0.0,"rh":71,"sky":"civil twilight","temp":-0.1,"time":"06:00","wind":1.5}],"peak_quality":1.0,"peak_sky":1.0,"quality_hours":4.18,"reasons":["daylight and twilight cost 2.7 quality-hours","moonlight cost 2.1 quality-hours","cloud cover cost 1.3 quality-hours"],"reference_hours":4.0,"score":76,"score_astronomy":100,"score_weather":76,"sky_hours":5.5,"verdict":"good","verdict_astronomy":"good","weather_known":true,"windows":[{"end":"2026-04-24T17:45Z","end_local":"20:45","hours":0.58,"label":"unusable","mean_quality":0.0,"start":"2026-04-24T17:10Z","start_local":"20:10"},{"end":"2026-04-24T20:00Z","end_local":"23:00","hours":2.25,"label":"poor","mean_quality":0.18,"start":"2026-04-24T17:45Z","start_local":"20:45"},{"end":"2026-04-24T23:00Z","end_local":"02:00","hours":3.0,"label":"marginal","mean_quality":0.43,"start":"2026-04-24T20:00Z","start_local":"23:00"},{"end":"2026-04-25T00:00Z","end_local":"03:00","hours":1.0,"label":"good","mean_quality":0.68,"start":"2026-04-24T23:00Z","start_local":"02:00"},{"end":"2026-04-25T00:30Z","end_local":"03:30","hours":0.5,"label":"marginal","mean_quality":0.55,"start":"2026-04-25T00:00Z","start_local":"03:00"},{"end":"2026-04-25T01:45Z","end_local":"04:45","hours":1.25,"label":"good","mean_quality":0.89,"start":"2026-04-25T00:30Z","start_local":"03:30"},{"end":"2026-04-25T02:25Z","end_local":"05:25","hours":0.67,"label":"marginal","mean_quality":0.5,"start":"2026-04-25T01:45Z","start_local":"04:45"},{"end":"2026-04-25T03:00Z","end_local":"06:00","hours":0.58,"label":"poor","mean_quality":0.15,"start":"2026-04-25T02:25Z","start_local":"05:25"},{"end":"2026-04-25T03:30Z","end_local":"06:30","hours":0.5,"label":"unusable","mean_quality":0.0,"start":"2026-04-25T03:00Z","start_local":"06:00"}]},"calculation_version":"2026-10-10.1","forecast":[{"cloud":64,"dark":false,"high":64,"local":"20:00","low":0,"mid":0,"precip":0.0,"rh":63,"temp":2.9,"time":"2026-04-24T17:00Z","wind":2.4},{"cloud":43,"dark":false,"high":43,"local":"21:00","low":0,"mid":0,"precip":0.0,"rh":63,"temp":2.2,"time":"2026-04-24T18:00Z","wind":1.3},{"cloud":45,"dark":true,"high":45,"local":"22:00","low":0,"mid":0,"precip":0.0,"rh":64,"temp":1.8,"time":"2026-04-24T19:00Z","wind":0.7},{"cloud":44,"dark":true,"high":43,"local":"23:00","low":2,"mid":0,"precip":0.0,"rh":66,"temp":0.9,"time":"2026-04-24T20:00Z","wind":1.3},{"cloud":32,"dark":true,"high":25,"local":"00:00","low":9,"mid":0,"precip":0.0,"rh":67,"temp":0.4,"time":"2026-04-24T21:00Z","wind":2.4},{"cloud":16,"dark":true,"high":13,"local":"01:00","low":4,"mid":0,"precip":0.0,"rh":65,"temp":0.7,"time":"2026-04-24T22:00Z","wind":2.6},{"cloud":5,"dark":true,"high":5,"local":"02:00","low":0,"mid":0,"precip":0.0,"rh":66,"temp":0.7,"time":"2026-04-24T23:00Z","wind":2.8},{"cloud":24,"dark":true,"high":24,"local":"03:00","low":0,"mid":0,"precip":0.0,"rh":67,"temp":0.9,"time":"2026-04-25T00:00Z","wind":0.9},{"cloud":0,"dark":true,"high":0,"local":"04:00","low":0,"mid":0,"precip":0.0,"rh":67,"temp":0.7,"time":"2026-04-25T01:00Z","wind":1.0},{"cloud":0,"dark":false,"high":0,"local":"05:00","low":0,"mid":0,"precip":0.0,"rh":68,"temp":0.4,"time":"2026-04-25T02:00Z","wind":1.0},{"cloud":0,"dark":false,"high":0,"local":"06:00","low":0,"mid":0,"precip":0.0,"rh":71,"temp":-0.1,"time":"2026-04-25T03:00Z","wind":1.5},{"cloud":0,"dark":false,"high":0,"local":"07:00","low":0,"mid":0,"precip":0.0,"rh":73,"temp":0.1,"time":"2026-04-25T04:00Z","wind":1.8}],"forecast_source":"history","forecast_updated_at":"2026-10-14T07:01:22Z","limits":{"good_alt":30.0,"usable_alt":20.0},"night":{"dark_from":"2026-04-24T18:55:45Z","dark_hours":6.77,"dark_to":"2026-04-25T01:41:59Z","moon":{"illumination":0.59,"phase":"waxing gibbous","waxing":true},"moon_free_dark_hours":1.23,"moonrise":"2026-04-24T09:43:44Z","moonset":"2026-04-25T00:26:07Z","sunrise":"2026-04-25T03:26:15Z","sunset":"2026-04-24T17:11:26Z","twilight":{"astronomical":{"end":"2026-04-24T18:55:45Z","start":"2026-04-25T01:41:59Z"},"civil":{"end":"2026-04-24T17:41:05Z","start":"2026-04-25T02:56:36Z"},"nautical":{"end":"2026-04-24T18:17:06Z","start":"2026-04-25T02:20:37Z"}},"window_end":"2026-04-25T09:00:00Z","window_start":"2026-04-24T09:00:00Z"},"night_date":"2026-04-24","site":{"elev_m":1750,"lat":41.693,"lon":24.739,"name":"NAO Rozhen"},"warnings":[]}