{"assessment":{"best_window":{"end":"2026-11-21T03:40Z","end_local":"05:40","hours":3.5,"label":"good","mean_quality":0.88,"start":"2026-11-21T00:10Z","start_local":"02:10"},"cost":{"altitude":0.0,"clouds":0.0,"darkness":2.62,"moon":4.72},"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":"Astronomically worth it \u2014 weather unknown","hourly":[{"alt":null,"cloud":null,"high":null,"iso":"2026-11-20T15:00Z","label":"unusable","low":null,"mid":null,"moon_alt":29,"precip":null,"q":0.0,"rh":null,"sky":"civil twilight","temp":null,"time":"17:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2026-11-20T16:00Z","label":"poor","low":null,"mid":null,"moon_alt":39,"precip":null,"q":0.07,"rh":null,"sky":"nautical twilight","temp":null,"time":"18:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2026-11-20T17:00Z","label":"marginal","low":null,"mid":null,"moon_alt":47,"precip":null,"q":0.43,"rh":null,"sky":"night","temp":null,"time":"19:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2026-11-20T18:00Z","label":"marginal","low":null,"mid":null,"moon_alt":52,"precip":null,"q":0.41,"rh":null,"sky":"night","temp":null,"time":"20:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2026-11-20T19:00Z","label":"marginal","low":null,"mid":null,"moon_alt":54,"precip":null,"q":0.41,"rh":null,"sky":"night","temp":null,"time":"21:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2026-11-20T20:00Z","label":"marginal","low":null,"mid":null,"moon_alt":50,"precip":null,"q":0.42,"rh":null,"sky":"night","temp":null,"time":"22:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2026-11-20T21:00Z","label":"marginal","low":null,"mid":null,"moon_alt":43,"precip":null,"q":0.44,"rh":null,"sky":"night","temp":null,"time":"23:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2026-11-20T22:00Z","label":"marginal","low":null,"mid":null,"moon_alt":34,"precip":null,"q":0.48,"rh":null,"sky":"night","temp":null,"time":"00:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2026-11-20T23:00Z","label":"marginal","low":null,"mid":null,"moon_alt":24,"precip":null,"q":0.53,"rh":null,"sky":"night","temp":null,"time":"01:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2026-11-21T00:00Z","label":"marginal","low":null,"mid":null,"moon_alt":14,"precip":null,"q":0.59,"rh":null,"sky":"night","temp":null,"time":"02:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2026-11-21T01:00Z","label":"good","low":null,"mid":null,"moon_alt":3,"precip":null,"q":0.65,"rh":null,"sky":"night","temp":null,"time":"03:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2026-11-21T02:00Z","label":"good","low":null,"mid":null,"moon_alt":-7,"precip":null,"q":1.0,"rh":null,"sky":"night","temp":null,"time":"04:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2026-11-21T03:00Z","label":"good","low":null,"mid":null,"moon_alt":-17,"precip":null,"q":1.0,"rh":null,"sky":"night","temp":null,"time":"05:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2026-11-21T04:00Z","label":"marginal","low":null,"mid":null,"moon_alt":-26,"precip":null,"q":0.5,"rh":null,"sky":"astronomical twilight","temp":null,"time":"06:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2026-11-21T05:00Z","label":"unusable","low":null,"mid":null,"moon_alt":-33,"precip":null,"q":0.0,"rh":null,"sky":"civil twilight","temp":null,"time":"07:00","wind":null}],"peak_quality":1.0,"peak_sky":1.0,"quality_hours":7.08,"reasons":["moonlight cost 4.7 quality-hours","daylight and twilight cost 2.6 quality-hours"],"reference_hours":4.0,"score":null,"score_astronomy":100,"score_weather":null,"sky_hours":7.08,"verdict":"unknown","verdict_astronomy":"good","weather_known":false,"windows":[{"end":"2026-11-20T15:30Z","end_local":"17:30","hours":0.58,"label":"unusable","mean_quality":0.0,"start":"2026-11-20T14:55Z","start_local":"16:55"},{"end":"2026-11-20T16:35Z","end_local":"18:35","hours":1.08,"label":"poor","mean_quality":0.14,"start":"2026-11-20T15:30Z","start_local":"17:30"},{"end":"2026-11-21T00:10Z","end_local":"02:10","hours":7.58,"label":"marginal","mean_quality":0.46,"start":"2026-11-20T16:35Z","start_local":"18:35"},{"end":"2026-11-21T03:40Z","end_local":"05:40","hours":3.5,"label":"good","mean_quality":0.88,"start":"2026-11-21T00:10Z","start_local":"02:10"},{"end":"2026-11-21T04:15Z","end_local":"06:15","hours":0.58,"label":"marginal","mean_quality":0.5,"start":"2026-11-21T03:40Z","start_local":"05:40"},{"end":"2026-11-21T04:50Z","end_local":"06:50","hours":0.58,"label":"poor","mean_quality":0.15,"start":"2026-11-21T04:15Z","start_local":"06:15"},{"end":"2026-11-21T05:20Z","end_local":"07:20","hours":0.5,"label":"unusable","mean_quality":0.0,"start":"2026-11-21T04:50Z","start_local":"06:50"}]},"calculation_version":"2026-10-10.1","forecast":[],"forecast_source":"none","forecast_updated_at":null,"limits":{"good_alt":30.0,"usable_alt":20.0},"night":{"dark_from":"2026-11-20T16:34:05Z","dark_hours":11.09,"dark_to":"2026-11-21T03:39:47Z","moon":{"illumination":0.824,"phase":"waxing gibbous","waxing":true},"moon_free_dark_hours":2.37,"moonrise":"2026-11-20T12:21:24Z","moonset":"2026-11-21T01:16:23Z","sunrise":"2026-11-21T05:17:08Z","sunset":"2026-11-20T14:56:56Z","twilight":{"astronomical":{"end":"2026-11-20T16:34:05Z","start":"2026-11-21T03:39:47Z"},"civil":{"end":"2026-11-20T15:27:09Z","start":"2026-11-21T04:46:51Z"},"nautical":{"end":"2026-11-20T16:01:04Z","start":"2026-11-21T04:12:52Z"}},"window_end":"2026-11-21T10:00:00Z","window_start":"2026-11-20T10:00:00Z"},"night_date":"2026-11-20","site":{"elev_m":1750,"lat":41.693,"lon":24.739,"name":"NAO Rozhen"},"warnings":["No cloud data for this night (beyond the 4-day forecast, or not yet in the archive) \u2014 the score is geometry only."]}
