{"assessment":{"best_window":{"end":"2026-11-24T19:15Z","end_local":"21:15","hours":2.67,"label":"marginal","mean_quality":0.38,"start":"2026-11-24T16:35Z","start_local":"18:35"},"cost":{"altitude":0.0,"clouds":0.0,"darkness":2.66,"moon":8.23},"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 possible, with compromises \u2014 weather unknown","hourly":[{"alt":null,"cloud":null,"high":null,"iso":"2026-11-24T15:00Z","label":"unusable","low":null,"mid":null,"moon_alt":5,"precip":null,"q":0.0,"rh":null,"sky":"civil twilight","temp":null,"time":"17:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2026-11-24T16:00Z","label":"poor","low":null,"mid":null,"moon_alt":15,"precip":null,"q":0.25,"rh":null,"sky":"astronomical twilight","temp":null,"time":"18:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2026-11-24T17:00Z","label":"marginal","low":null,"mid":null,"moon_alt":25,"precip":null,"q":0.43,"rh":null,"sky":"night","temp":null,"time":"19:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2026-11-24T18:00Z","label":"marginal","low":null,"mid":null,"moon_alt":36,"precip":null,"q":0.37,"rh":null,"sky":"night","temp":null,"time":"20:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2026-11-24T19:00Z","label":"marginal","low":null,"mid":null,"moon_alt":47,"precip":null,"q":0.31,"rh":null,"sky":"night","temp":null,"time":"21:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2026-11-24T20:00Z","label":"poor","low":null,"mid":null,"moon_alt":57,"precip":null,"q":0.27,"rh":null,"sky":"night","temp":null,"time":"22:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2026-11-24T21:00Z","label":"poor","low":null,"mid":null,"moon_alt":67,"precip":null,"q":0.23,"rh":null,"sky":"night","temp":null,"time":"23:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2026-11-24T22:00Z","label":"poor","low":null,"mid":null,"moon_alt":74,"precip":null,"q":0.22,"rh":null,"sky":"night","temp":null,"time":"00:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2026-11-24T23:00Z","label":"poor","low":null,"mid":null,"moon_alt":73,"precip":null,"q":0.22,"rh":null,"sky":"night","temp":null,"time":"01:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2026-11-25T00:00Z","label":"poor","low":null,"mid":null,"moon_alt":65,"precip":null,"q":0.24,"rh":null,"sky":"night","temp":null,"time":"02:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2026-11-25T01:00Z","label":"poor","low":null,"mid":null,"moon_alt":55,"precip":null,"q":0.27,"rh":null,"sky":"night","temp":null,"time":"03:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2026-11-25T02:00Z","label":"marginal","low":null,"mid":null,"moon_alt":44,"precip":null,"q":0.32,"rh":null,"sky":"night","temp":null,"time":"04:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2026-11-25T03:00Z","label":"marginal","low":null,"mid":null,"moon_alt":34,"precip":null,"q":0.38,"rh":null,"sky":"night","temp":null,"time":"05:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2026-11-25T04:00Z","label":"poor","low":null,"mid":null,"moon_alt":23,"precip":null,"q":0.22,"rh":null,"sky":"astronomical twilight","temp":null,"time":"06:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2026-11-25T05:00Z","label":"unusable","low":null,"mid":null,"moon_alt":13,"precip":null,"q":0.0,"rh":null,"sky":"civil twilight","temp":null,"time":"07:00","wind":null}],"peak_quality":0.46,"peak_sky":0.46,"quality_hours":3.69,"reasons":["moonlight cost 8.2 quality-hours","daylight and twilight cost 2.7 quality-hours"],"reference_hours":4.0,"score":null,"score_astronomy":42,"score_weather":null,"sky_hours":3.69,"verdict":"unknown","verdict_astronomy":"marginal","weather_known":false,"windows":[{"end":"2026-11-24T15:25Z","end_local":"17:25","hours":0.58,"label":"unusable","mean_quality":0.0,"start":"2026-11-24T14:50Z","start_local":"16:50"},{"end":"2026-11-24T16:35Z","end_local":"18:35","hours":1.17,"label":"poor","mean_quality":0.16,"start":"2026-11-24T15:25Z","start_local":"17:25"},{"end":"2026-11-24T19:15Z","end_local":"21:15","hours":2.67,"label":"marginal","mean_quality":0.38,"start":"2026-11-24T16:35Z","start_local":"18:35"},{"end":"2026-11-25T01:35Z","end_local":"03:35","hours":6.33,"label":"poor","mean_quality":0.25,"start":"2026-11-24T19:15Z","start_local":"21:15"},{"end":"2026-11-25T03:45Z","end_local":"05:45","hours":2.17,"label":"marginal","mean_quality":0.36,"start":"2026-11-25T01:35Z","start_local":"03:35"},{"end":"2026-11-25T04:55Z","end_local":"06:55","hours":1.17,"label":"poor","mean_quality":0.15,"start":"2026-11-25T03:45Z","start_local":"05:45"},{"end":"2026-11-25T05:25Z","end_local":"07:25","hours":0.5,"label":"unusable","mean_quality":0.0,"start":"2026-11-25T04:55Z","start_local":"06:55"}]},"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":"2026-11-24T16:32:16Z","dark_hours":11.19,"dark_to":"2026-11-25T03:43:44Z","moon":{"illumination":0.997,"phase":"full moon","waxing":false},"moon_free_dark_hours":0.0,"moonrise":"2026-11-24T14:28:58Z","moonset":"2026-11-25T06:24:05Z","sunrise":"2026-11-25T05:21:46Z","sunset":"2026-11-24T14:54:26Z","twilight":{"astronomical":{"end":"2026-11-24T16:32:16Z","start":"2026-11-25T03:43:44Z"},"civil":{"end":"2026-11-24T15:24:56Z","start":"2026-11-25T04:51:12Z"},"nautical":{"end":"2026-11-24T15:59:04Z","start":"2026-11-25T04:16:59Z"}},"window_end":"2026-11-25T10:00:00Z","window_start":"2026-11-24T10:00:00Z"},"night_date":"2026-11-24","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."]}