{"assessment":{"best_window":{"end":"2026-11-24T03:45Z","end_local":"05:45","hours":3.42,"label":"marginal","mean_quality":0.4,"start":"2026-11-24T00:20Z","start_local":"02:20"},"cost":{"altitude":0.0,"clouds":0.0,"darkness":2.59,"moon":8.02},"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":"2026-11-23T15:00Z","label":"unusable","low":null,"mid":null,"moon_alt":13,"precip":null,"q":0.0,"rh":null,"sky":"civil twilight","temp":null,"time":"17:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2026-11-23T16:00Z","label":"poor","low":null,"mid":null,"moon_alt":23,"precip":null,"q":0.22,"rh":null,"sky":"astronomical twilight","temp":null,"time":"18:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2026-11-23T17:00Z","label":"marginal","low":null,"mid":null,"moon_alt":34,"precip":null,"q":0.38,"rh":null,"sky":"night","temp":null,"time":"19:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2026-11-23T18:00Z","label":"marginal","low":null,"mid":null,"moon_alt":45,"precip":null,"q":0.32,"rh":null,"sky":"night","temp":null,"time":"20:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2026-11-23T19:00Z","label":"poor","low":null,"mid":null,"moon_alt":56,"precip":null,"q":0.28,"rh":null,"sky":"night","temp":null,"time":"21:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2026-11-23T20:00Z","label":"poor","low":null,"mid":null,"moon_alt":65,"precip":null,"q":0.25,"rh":null,"sky":"night","temp":null,"time":"22:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2026-11-23T21:00Z","label":"poor","low":null,"mid":null,"moon_alt":70,"precip":null,"q":0.23,"rh":null,"sky":"night","temp":null,"time":"23:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2026-11-23T22:00Z","label":"poor","low":null,"mid":null,"moon_alt":69,"precip":null,"q":0.23,"rh":null,"sky":"night","temp":null,"time":"00:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2026-11-23T23:00Z","label":"poor","low":null,"mid":null,"moon_alt":62,"precip":null,"q":0.25,"rh":null,"sky":"night","temp":null,"time":"01:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2026-11-24T00:00Z","label":"poor","low":null,"mid":null,"moon_alt":53,"precip":null,"q":0.29,"rh":null,"sky":"night","temp":null,"time":"02:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2026-11-24T01:00Z","label":"marginal","low":null,"mid":null,"moon_alt":42,"precip":null,"q":0.34,"rh":null,"sky":"night","temp":null,"time":"03:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2026-11-24T02:00Z","label":"marginal","low":null,"mid":null,"moon_alt":31,"precip":null,"q":0.4,"rh":null,"sky":"night","temp":null,"time":"04:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2026-11-24T03:00Z","label":"marginal","low":null,"mid":null,"moon_alt":21,"precip":null,"q":0.46,"rh":null,"sky":"night","temp":null,"time":"05:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2026-11-24T04:00Z","label":"poor","low":null,"mid":null,"moon_alt":11,"precip":null,"q":0.27,"rh":null,"sky":"astronomical twilight","temp":null,"time":"06:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2026-11-24T05:00Z","label":"unusable","low":null,"mid":null,"moon_alt":1,"precip":null,"q":0.0,"rh":null,"sky":"civil twilight","temp":null,"time":"07:00","wind":null}],"peak_quality":0.51,"peak_sky":0.51,"quality_hours":3.89,"reasons":["moonlight cost 8.0 quality-hours","daylight and twilight cost 2.6 quality-hours"],"reference_hours":4.0,"score":null,"score_astronomy":49,"score_weather":null,"sky_hours":3.89,"verdict":"unknown","verdict_astronomy":"marginal","weather_known":false,"windows":[{"end":"2026-11-23T15:30Z","end_local":"17:30","hours":0.58,"label":"unusable","mean_quality":0.0,"start":"2026-11-23T14:55Z","start_local":"16:55"},{"end":"2026-11-23T16:35Z","end_local":"18:35","hours":1.08,"label":"poor","mean_quality":0.15,"start":"2026-11-23T15:30Z","start_local":"17:30"},{"end":"2026-11-23T18:30Z","end_local":"20:30","hours":1.92,"label":"marginal","mean_quality":0.35,"start":"2026-11-23T16:35Z","start_local":"18:35"},{"end":"2026-11-24T00:20Z","end_local":"02:20","hours":5.83,"label":"poor","mean_quality":0.25,"start":"2026-11-23T18:30Z","start_local":"20:30"},{"end":"2026-11-24T03:45Z","end_local":"05:45","hours":3.42,"label":"marginal","mean_quality":0.4,"start":"2026-11-24T00:20Z","start_local":"02:20"},{"end":"2026-11-24T04:55Z","end_local":"06:55","hours":1.17,"label":"poor","mean_quality":0.18,"start":"2026-11-24T03:45Z","start_local":"05:45"},{"end":"2026-11-24T05:25Z","end_local":"07:25","hours":0.5,"label":"unusable","mean_quality":0.0,"start":"2026-11-24T04:55Z","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":"2026-11-23T16:32:41Z","dark_hours":11.17,"dark_to":"2026-11-24T03:42:46Z","moon":{"illumination":0.991,"phase":"full moon","waxing":true},"moon_free_dark_hours":0.0,"moonrise":"2026-11-23T13:45:46Z","moonset":"2026-11-24T05:05:59Z","sunrise":"2026-11-24T05:20:37Z","sunset":"2026-11-23T14:55:01Z","twilight":{"astronomical":{"end":"2026-11-23T16:32:41Z","start":"2026-11-24T03:42:46Z"},"civil":{"end":"2026-11-23T15:25:26Z","start":"2026-11-24T04:50:07Z"},"nautical":{"end":"2026-11-23T15:59:31Z","start":"2026-11-24T04:15:58Z"}},"window_end":"2026-11-24T10:00:00Z","window_start":"2026-11-23T10:00:00Z"},"night_date":"2026-11-23","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."]}